economics

AQA GCSE Science: P1a 1.1 How can science help us see in the dark?
AQA Specification Link
• Thermal (infra-red) radiation is the transfer of energy by electromagnetic waves.
• All bodies emit and absorb thermal radiation.
• The hotter a body is the more energy it radiates.

Learning Objectives
Students should learn: • The nature of thermal radiation.
• That the amount of thermal radiation emitted increases with the temperature of the object.
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Seeing at night – Search the web for infra-red images, show them and see if the students can identify the objects. Can the students tell the hot parts from the cold? (5–10 minutes)
Hand warming – Ask students to draw a diagram explaining why holding your hands in front of a fire warms them up. (5 minutes)
How can you tell that something is hot? – What ways are there for identifying if an object is hot without touching it? (5 minutes)

Teacher Exposition
• Discuss how being in sunlight makes you feel warm while the shade can feel cool. Why is this?
• Discuss infra-red images and how all objects are giving off invisible infra-red radiation due to the thermal energy in them. Link the temperature of the object to the amount of energy emitted.
• Demonstrating the rise in temperature mentioned in the text requires a bright white light source. A sensitive thermometer or sensor should also be used.
• Discuss the meaning of the words ‘radiate’ (to spread out from a source) and ‘radiation’ (the energy that is spread) to make sure the students have a full understanding.
• Emphasise that there is empty space (a vacuum) between the Earth and the Sun and that infra-red radiation passes through this vacuum easily, otherwise we would receive no heat energy from the Sun.
• Check that the students can understand or draw a ray diagram showing this information.
• You can use a diagram to show how all of the energy is focused in a solar oven, pointing out that the rays travel in straight lines; just like visible light.
• As a simple alternative, a magnifying glass can be used to ignite a piece of paper to show how high temperatures can be reached.
• A discussion of the greenhouse effect is best presented using a diagram to point out what you mean by wavelength. Two diagrams can be used to link the greenhouse effect with a real greenhouse.
• Check that students do not link the greenhouse effect with ozone; this is a common misconception.
Pupil development

Plenaries
Temperature order – Show a list of objects or materials (e.g. Sun’s surface, boiling water, etc.) and get the students to put them in temperature order. (5 minutes)

Teaching suggestions

• Special needs. Incomplete diagrams explaining the greenhouse effect should be provided for the students to finish.

• Gifted and talented. Infra-red satellite imagery is used in weather forecasting and analysis of land use. These students could investigate how IR satellites are used to monitor the weather and to analyse how land is used in different countries. They could find out how different types of vegetation or habitation show up in infra-red imagery or even other parts of the electromagnetic spectrum. There are many excellent images available to explore on the Internet; they could start with the various ‘landsat’ or weather forecasting web sites.

• Learning styles
Kinaesthetic: Placing objects in temperature order.
Visual: Observing IR images and the solar oven demonstration. Auditory: Listening to ideas of others on uses of IR cameras and sunlight. Interpersonal: Discussing the way heat reaches the Earth. Intrapersonal: Making deductions about the amount of energy emitted by an object.

Learning Outcomes
Most students should be able to:
• State that there is radiation, similar to light but invisible, that is emitted by all objects.
• Explain that the hotter an object is the more infra-red radiation it emits.
• Describe thermal radiation as electromagnetic waves.

Practical support
Demonstrating infra-red radiation
You may want to do this as a demonstration if you don’t want to coat a lot of thermometers with paint.
Equipment and materials required
For each group: bright white light source (power supply and ray box), sensitive thermometer (to 0.5 °C) with bulb painted matt black, clean prism.
Details
Shine the light through the prism and produce the spectrum (this could be projected on the wall if you are just demonstrating). Position the thermometer just beyond the red part of the spectrum and the temperature reading will rise.
Demonstrating a solar oven
Small solar ovens are available and can be used to boil small quantities of water. As an alternative, an old parabolic car headlight can be used. If a match is mounted at the focus of the parabola (this takes some practice) and the headlight is pointed towards a bright light source (such as the Sun or another headlight) the match will ignite.

Activities and extensions
Measuring IR radiation
• The amount of radiation produced by a hot object can be measured with an IR probe and a data logger.
Equipment and materials required Data logging systems with IR probes, 12 V bulbs and variable power supplies (or variable resistors) to produce varying currents.
Details
The students could investigate the amount of IR energy produced by a bulb with different currents and so different temperatures. By changing the current through the bulb, the temperature increases and so should the amount of IR radiation emitted.

AQA GCSE Science: P1a 1.2 Why are white tee shirts better than black ones on a hot sunny day?
AQA Specification Link
• Dark, matt surfaces are good absorbers and good emitters of radiation.
• Light, shiny surfaces are poor absorbers and poor emitters of radiation.
Learning Objectives
Students should learn:
• Matt black surfaces are the best emitters and absorbers of thermal radiation.
• Silver surfaces are the worst emitters and absorbers of thermal radiation.

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Out in the sun – Discuss with students how it feels to go out in a black tee shirt on a sunny day or, alternatively, what it is like getting into a black car on a sunny day. Ask them to explain why they think they feel hotter. (5 minutes)
Definitions – Show the students the key words for this spread (absorb, reflect, emit) and ask them to write down their own definitions. (5–10 minutes)
Polar bears – Ask the students what colour polar bears are and list reasons for this. (5 minutes)

Teacher Exposition
• Most students will understand that the inside of a black car feels very hot on a sunny day, so start with these ideas about heating.
• A Leslie’s cube is ideal to demonstrate that two surfaces at the same temperature can give off different amounts of thermal radiation. An infra-red sensor can be used to detect levels of IR radiation from the cube.
• The difference is easily felt by placing the back of the hand a few centimetres from the surfaces, but care must be taken that the students do not actually touch the surface.
• Watch out for misunderstanding of the word ‘absorb’; many students have the impression that it means that the surface somehow ‘sucks in’ the energy from its surroundings. • This spread presents an early opportunity for assessing the students’ practical skills.
They need to know that these skills are being monitored and will form part of their final grade.
• You can also introduce some of the concepts covered in ‘How Science Works’ in this lesson, e.g. the nature of different types of variable, how to present results and evaluating the design of investigations.
• If time is available, and you plan to try both practical activities, then the students should be able to use the same equipment for both. If time is short, then half the students can do one of the practical tasks while the other half does the second. They can share results and ideas at the end.
• After the emission practical, check that the students actually achieved the results you expected; the difference in temperature can be small and it is not unusual to reach the wrong conclusion.
• Discuss how to improve the practical to make it more fair or accurate. • The second practical works best on very sunny days, you may need to start it early on dull days and leave it running for a while.
• Check understanding of both the absorption and emission practicals and, in particular, correct use of the key words.
Pupil Development

Plenaries
Choosing the right colour – Give the students a series of simple scenarios, such as ‘What colour cup should you use to keep orange juice cold on a hot day?’ and ask them to give reasons. (5 minutes) Without words – Ask the students to draw illustrations showing that black surfaces are better emitters and absorbers, without using any words. (5 minutes)

Teaching suggestions
• Learning styles
Visual: Looking at the heating and cooling results displayed graphically.
Auditory: Discussing why objects are painted different colours and the experiment’s results.
Interpersonal: Giving feedback about results. Intrapersonal: Evaluating outcome of experiment.
Kinaesthetic: Doing practical activities.
• Teaching assistant. Use responsible pupilsThe teaching assistant could manage the queue to test out the Leslie’s cube while you move on.
• ICT link-up. Use data loggers and temperature sensors for the practical work when possible. These are easy to operate and produce far more detailed evidence of heating and cooling. The students can spend much more time on analysing the evidence instead of plotting graphs for every experiment.

Learning Outcomes
Most students should be able to:
• Describe which surfaces are the best emitters of thermal radiation.
• Describe which surfaces are the best absorbers of radiation.

Some students should also be able to:
• Explain how the choice of a surface colour can affect the rate of temperature change of an object.

Activities and extensions
The cooling experiment can be expanded into a more detailed investigation allowing assessment of the students’ skills.
A coffee conundrum
A cup of coffee is left for 10 minutes to cool down. Would the coffee end up cooler if the milk was poured in immediately after it was made, or after 5 minutes? (This makes an ideal data logging investigation.)
Equipment and materials required
Two identical cups, coffee powder, milk, kettle and data loggers.
Leslie’s cube
The Leslie’s cube was devised by Sir John Leslie to demonstrate the importance of surface colour on the radiation of energy. With data-logging equipment, the experiment can be expanded to show that the dull black surface always radiates more energy than the silver one and that the amount of energy radiated depends on the temperature of the water in the cube.
Equipment and materials required
Leslie’s cube), kettle.
Details
Set up the cube with two IR sensors one 5cm from the matt black surface and another 5cm from the silver one. Place a temperature probe into the container and add boiling water (take care!). Record the cooling of the container and the amount of energy radiated from the surfaces over a period of up to half an hour. The students can then analyse the results and reach conclusions about the relationships. If only one IR probe is available, the students can describe the relationship between the temperature and the amount of energy radiated by each surface separately; to save time record some data in advance for comparison.

Practical support
Testing different surfaces
Equipment and materials required
Kettles or another way of heating water. For each group: two beakers, two thermometers (to 0.5 °C), aluminium foil and black card, elastic bands (to hold the card on), stopclock, a measuring cylinder.
Details
It’s possible to use painted beakers or boiling tubes as in the absorption tests activity below. It is essential to use lids on the containers to reduce evaporation; aluminium foil works well and the thermometers can be poked through it to get a good seal. Higher starting temperatures give greater temperature drops in reasonable times but the students will need to be extra careful with hot water.
Absorption tests
Equipment and materials required
For each group: two coloured beakers, two thermometers (to 0.5°C), heat-resistant mat.
Details
The beakers should be painted in advance; aerosol car paint works very well and is available in matt black, chrome silver and other colours. Two coats of paint seem to work better than one and it is possible to get decent results by substituting boiling tubes for the beakers.

AQA GCSE Science: P1a 1.3 Why do some saucepans have plastic handle?
AQA Specification Link
• The transfer of energy by conduction . . . involves particles and how this transfer takes place.
• Under similar conditions different materials transfer heat at different rates.
Learning Objectives
Students should learn: • Metals are good thermal conductors because they have free electrons that carry energy.
• Non-metals solids are generally poor conductors because they rely on atomic vibrations to carry energy.

Teaching / Learning activities (including How Science Works)
Lesson structure
Starter
The wooden spoon – Ask the students to come up with an explanation of why it is alright to leave a wooden spoon in a pan of soup when heating it, but not a metal spoon. (5 minutes)
A heat-proof mat – Is a heat-proof mat really heat-proof? The students design an experiment to find out just how heat-resistant the material is. (10 minutes)

Teacher Exposition
• Carry out the testing rods activity. Adding drawing pins attached to the end of the rods with petroleum jelly, so that they fall off when the jelly melts, gives a touch of drama.
• If you tried the heat-proof mat starter, you could show how slowly the mat conducts by heating a cube of ice with a Bunsen through a mat sitting on a tripod.
• The conduction/insulation practical is a fairly simple concept but is quite fiddly to do successfully. Give the students adequate time to set it up carefully and then get readings (5–10 minutes of cooling).
• The students should be encouraged to make accurate and precise readings during the experiment and this would be an excellent time to introduce data logging as an alternative to watching a thermometer for a long time.
• After the practical, the students should be able to tell you which material was the best conductor and which was the worst.
• This lesson gives another opportunity to cover aspects of ‘How Science Works’, e.g. the reliability of data collected, the nature of variables and experimental design.
• The poor conductivity of air can be shown by holding an ice cube (in tongs) alongside a Bunsen flame, where it melts only slowly, and then a few centimetres above the top of the flame.
• The concept of free electrons will be unfamiliar to many students. A visual approach with animation is ideal for introducing this concept. For example, use the animation, P1a 1.3 ‘Conduction of heat’, from the GCSE Science CD.
• An analogy, such as students staying in their place (representing ions in a metal) and throwing objects to each other (representing electrons carrying thermal energy), can be used with the right kind of group.
• After explaining this, the students should be able to tell you what the electrons do to get energy from one end to the other.
• Conduction by lattice vibration again requires clear diagrams to picture this idea. An ionic lattice model (e.g. sodium chloride) can help a lot here.
Pupil Devlopment

Plenaries
A model for conduction – Challenge the students to come up with an analogy for lattice vibration, to give them a visual idea of what is going on. They could come up with holding each other at arm’s length and passing a shake along a line. (5–10 minutes)
An electron story – Students describe their experience as an electron in a metal rod being heated at one end. (5–10 minutes)

Teaching suggestions
• Learning styles
Kinaesthetic: Carrying out a range of experiments.
Visual: Obtaining precise results.
Auditory: Explaining and listening to the outcomes of experiments from different groups.
Interpersonal: Evaluating the quality of results.
Intrapersonal: Making a conduction model analogy.
• Teaching assistant. The teaching assistant could support students who have physical or coordination difficulties with practical work. It is especially important to keep the containers dry.
• Homework. List the materials used for insulation in your own home and where they are found. Why are these materials chosen?
Learning Outcomes
Most students should be able to:
• State that metals are good conductors of thermal energy.
• List poor conductors or insulators.

Some students should also be able to:
• Explain why metals are good conductors of thermal energy in terms of electron behaviour.
Practical support
Conducting rods
Equipment and materials required
As a demonstration: set of metal rods with wax/petroleum jelly on one end (aluminium, copper, steel, brass and possibly glass), drawing pins, Bunsen burner, tripod, heat-resistant mat, eye protection.
Details
• Aluminium’s melting point is lower than the temperature of a blue Bunsen flame, so be careful not to melt the aluminium rod. A glass rod can be heated strongly until the glass is red hot and yet the other end is still cool demonstrating just how poor a conductor it is.
Testing sheets of material
Equipment and materials required
Kettles or another way of heating water. For each group: two containers (beakers or metal cans), two thermometers (to 0.5 °C), sample materials (cotton wool, felt, paper, foam, etc.), two elastic bands, stop clock and a 100cm3 measuring cylinder.
Details
It can be difficult to control this experiment because the materials are different thicknesses, and if the materials get wet a lot of energy is lost through the process of evaporation. Make sure that the students take care in lagging the containers and that they are on an insulated base, otherwise much of the energy is conducted into the bench. When carrying out practicals using cans of water, it is essential to use covers as heat loss by evaporation is significant and will affect the results. The experiment works best with hotter water, but this increases the hazards.
Safety: Take care as some objects remain hot for a considerable time.
Activities and extensions
• The insulation experiment can be expanded to investigate the effectiveness of different thicknesses of materials, e.g. are two layers of felt twice as good as one? (Varying the ‘number of layers’ is an example of an investigation in which the independent variable is a discrete variable – see ‘How Science Works’.)
• Why do blocks of cold metal feel colder than blocks of cold wood? Give the students some blocks straight from the freezer and ask them to explain the difference.

AQA GCSE Science: P1a 1.4 How is a radiator able to heat a whole room?
AQA Specification Link
• The transfer of energy by . . . convection involves particles and how this transfer takes place.
• Under similar conditions different materials transfer heat at different rates.
Learning Objectives
Students should learn: How convection current carry thermal energy in fluids.
• How expansion and changes in density cause convection currents.
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Density demonstration – Demonstrate the expansion of a material when heated (mercury in a thermometer, a ball and chain, etc.) and ask the students to explain what is happening in terms of particle behaviour. (10 minutes)
What is a fluid? – The students list the properties of solids, liquids and gases to check their understanding of the particle model. (10 minutes)

Teacher Exposition
• Emphasise the fact that a fluid is a substance where the particles can move past each other so both gases and liquids are fluid. Because gases have completely separated particles, these can flow faster than liquids.
• Demonstrating the chimney effect with the apparatus shown in the diagram is very helpful. Brown corrugated card produces a lot of fine smoke when it is stubbed out, and the students can see the flow of smoke down the first chimney and up the second.
• If you have convection heaters, you can demonstrate (or let the students have a go at making) spirals of paper hung on string. These move due to the current above the heater. Don’t leave big ones up because they can set off motion sensitive alarms in the middle of the night!
• Convection currents in water can be shown using a small potassium permanganate crystal placed carefully in the corner of a convection ring, and heating gently using a Bunsen burner in one corner is much better.
• The students need to go through the stages that cause a convection current with emphasis on the use of the correct words at each stage. They could label a diagram or draw a flow chart after viewing the animation, P1a 1.4 ‘Air flow and convection’, from the GCSE Science CD.
• Make sure that they are using the terms ‘expand’ and ‘contract’ correctly before the plenary.
Pupil Development

Plenaries
The sea by night – Using the ideas from this lesson, the students can draw a diagram and give an explanation about why there is a breeze from the land to the sea in the evening at the coast. (5 minutes)
Heat transfer diagram – Let the students draw a mind map linking their ideas about conduction, convection and radiation. (10 minutes)

Teaching suggestions
• Special needs. Students could use worksheets with the processes in a convention current mixed up. They can cut these up and stick them in their books in the correct sequence.
• Learning styles
Kinaesthetic: Making convection mobiles.
Visual: Observing convection currents and visualising particle behaviour.
Auditory: Explaining the sea breeze.
Interpersonal: Reporting on the cause of coastal breezes. Intrapersonal: Making deductions about particle behaviour.
• Homework. Convection currents are very important in the oceans and dramatically affect the weather of the British Isles. Compare London’s winter to Moscow’s. The students could research the effect of the Gulf Stream and what the weather would be like without it. As an alternative, they could find out about El Niño.
• ICT link-up. Use animations to show the behaviours of solids, liquids and gases as they are heated and expand.

Learning Outcomes
Most students should be able to:
• Give examples of where convection currents occur.
• Describe the process of convection in terms of particle movement in liquids and gases, and explain why convection cannot happen in solids.

Some students should also be able to:
• Give a detailed description of convection in terms of particle movement, expansion and density changes.

Practical support
Chimney effect
The chimney apparatus is fairly standard, but can be improvised if necessary. The container must have a glass or Perspex front, so that air cannot enter from this route. Point out to students that using a fire with a chimney is the cause of some drafts in houses.
Demonstrating convection in liquids
• The potassium manganate(VII) can be placed at the bottom of the beaker by the following method so that it does not dissolve as it falls: Fill the beaker with water. Place your thumb over the end of a glass tube and push it into the beaker so that it touches the bottom and doesn’t let any water in. Take your thumb off and, hopefully, the tube will remain empty. Finally drop the crystal down the tube using forceps and remove the tube. Then you should get a perfectly placed crystal.
• With a glass convection loop, the crystal should be placed at the top and the tube heated at the bottom. Don’t try to get it in the bottom corner.
Safety: Potassium manganate(VII) is harmful. Its crystals will stain hands and clothing. Handle crystals with tweezers. KEY POINTS

Activities and extensions
• The Galilean thermometer relies on changes of density in liquids and solids to show temperature. Ask the students to come up with an explanation of how the thermometer works.
• Demonstrate, or allow the students to find out about, conduction and convection in water. Hold a small ice cube at the bottom of a boiling tube with a bit of metal gauze and three-quarters fill the tube with water. Heat the water strongly in the middle of the tube with a Bunsen; the water at the top will boil while the ice remains frozen. Ask the students to explain this in terms of conduction and convection.

AQA GCSE Science: P1a 1.5 Why does a hot cup of tea get cold?
AQA Specification Link
• Under similar conditions different materials transfer heat at different rates.
• The shape and dimensions of a body affect the rate at which it transfers heat.
• The bigger the temperature difference between a body and its surroundings, the faster the rate at which heat is transferred.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to evaluate ways in which heat is transferred in and out of bodies, and ways in which the rates of these transfers can be reduced.
Learning Objectives
Students should learn: • The factors that affect the rate of thermal energy transfer.
• That understanding thermal energy transfer allows us to design ways of controlling the flow of thermal energy.
• How this understanding can be used to reduce or increase thermal energy transfer in a variety of situations.

Teaching / Learning activities (including How Science Works)
Lesson structure
Starter
Keeping warm – How could you keep a cup of tea warm? The students should come up with some ideas. (10 minutes)
Cooling down – How can a substance be cooled quickly? (10 minutes)

Teacher Exposition
• With the students watching, fill a glass beaker and a vacuum flask with the same volume of boiling water at the start of the lesson for later.
• If a radiator from a small refrigerator is available, this makes an excellent prop to discuss how to design an object to give out thermal energy quickly. Emphasise the way the surface area is maximised to allow air to flow and carry away thermal energy. • You can discuss how a cup of tea can be cooled by blowing over it, although this also involves evaporation.
• Students can investigate the difference in cooling for objects with a large surface area and those with a small surface area, as described in ‘Practical support’. You can leave this running while moving on to the vacuum flask demonstration. Others can look at different initial temperatures. All investigative aspects of ‘How Science Works’ can be covered here.
• Some students will struggle in understanding that the larger beaker has a smaller surface area to volume ratio. Cubic containers may help the students, if some are available.
• Vacuum flasks in various states of construction (without the silvering) can be shown to explain their features. It is important to emphasise that there is no air between the glass walls; show them the point where the air has been sucked out before sealing.
• Show the students the difference in temperature of the water in the cup and the flask to illustrate how good the flask is at keeping water hot. Check that the students can describe what each feature of the flask does to prevent heat loss. • The students should have little difficulty explaining how heat loss can be reduced in houses and could produce a simple summary of the effects. In the next lesson, they will prioritise which methods to use first based on pay back time.
Pupil Development

Plenaries
Warming up the lab – The students can list or design improvements to prevent heat loss from the laboratory. (5 minutes)
How does the flask know? – A vacuum flask also keeps cold contents cold. Ask the students to explain how. (10 minutes)

Teaching suggestions
• Gifted and talented. These students should be calculating the volume to surface area ratio of the containers.
• Learning styles Kinaesthetic: Doing practical activities.
Visual: Making observations and presenting data.
Auditory: Explaining the operation of a vacuum flask.
Interpersonal: Discussing how objects cool down.
Intrapersonal: Evaluating and giving feedback about experiments.
• ICT link-up. Use temperature sensors and data logging software to capture more detail and save time plotting the graphs in the experiments.

Learning Outcomes
Most students should be able to:
• Investigate factors that affect the rate of thermal energy transfer.
• Describe how thermal energy transfer is reduced in houses to keep them warm.

Some students should also be able to:
• Explain, in detail, how the design of a vacuum flask reduces thermal energy transfer.

Practical support
Demonstrating the effectiveness of a vacuum flask
Equipment and materials required
Vacuum flask, kettle, similarly sized beaker, two thermometers.
Details
Fill the flask and beaker with the same volume of boiling water. Put the lid on the flask and allow the containers to cool for as long as possible during the lesson. The flask will keep the water very hot, usually above 80 °C, while the beaker will be quite cool. For an even greater difference leave the beaker on a conductive surface.
Investigating the rate of heat transfer
Equipment and materials required
Large (500cm3) and small (250cm3) glass beakers, data loggers, temperature sensors, thermometers, Bunsen burners, mats and tripods, aluminium foil for lids, eye protection.
Details
Fill the beakers with hot water and then boil the water with the Bunsen to make sure that they both start at the same temperature. Turn off the Bunsen burners, carefully add a foil lid and monitor the cooling for 10 minutes. The smaller beaker should cool substantially more than the larger one. These ideas can lead to a more complete investigation of the relationship between surface area and cooling. Students can then investigate if the temperature difference between the water and its surroundings affects its rate of cooling.

Activities and extensions
• Computer components become exceptionally hot and this thermal energy needs to be removed. The microprocessor will have a cooling system and the case will be designed to allow energy to be convected out. You could open up the case of a PC and explain how the cooling systems work in terms of conduction, convection and radiation.
Safety: Ensure PC cannot be plugged into the mains.
• Sir James Dewar invented the vacuum flask (or Dewar Jar). The students could research the history of this and his other important chemical discoveries.

AQA GCSE Science: P1a 2.1 forms of energy
AQA Specification Link
• Energy can only be transformed from one form to another form.
Learning Objectives
Students should learn: • The words commonly used to describe energy in a range of situations.
• To describe how energy is transfered in common situations.
• That gravitational potential energy and kinetic energy are often transferred.

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
What is energy? – Ask students to express their ideas about what the word ‘energy’ means. (5–10 minutes)
How can we describe energy? – Get the students to produce a list of the words that they have used in Key Stage 3 to describe energy and give an example of how to use each word. (5 minutes)
Off like a rocket – Show the students a video of a firework rocket (search for ‘fireworks’ at www.video.google.com). Ask them to draw an energy transfer diagram of what they see happening.
(5 minutes)

Teacher Exposition Pupil Devlopment
• Fuels are a familiar form of chemical energy and sample fuels should be made available for the students to look at.
• Most students will already be aware of many of the words used to describe energy. Ask them to write out a complete list of these words with an example showing each one. The ‘correct’ list should be: ‘thermal (heat), light, sound, electrical, kinetic (movement), chemical, gravitational potential, elastic/strain, nuclear’.
• Some students tend to think of ‘potential’ as a form of energy all on its own and not just a way of describing stored energy, e.g. ‘strain’ and ‘chemical’ are both potential energy. This misconception should be corrected at this point.
• An apple (or board duster) is a handy prop for discussing gravitational potential energy. They have around 1J of gravitational potential energy when held 1m off the floor.
• Dropping something large to ensure it makes a loud noise shows the energy transfer from gravitational potential to sound and thermal.
• Energy transfer diagrams (or Sankey diagrams) are very common and the students should draw a number of them. It is important that they label these only with the correct terms.
• After discussing the forms of energy, allow the students to explore simple energy transfers in an energy circus as described in ‘Practical support’.
• Make sure that the students have described the correct energy transfer for each of the devices.
• It is always worth demonstrating the heating effect of a current in a wire. Use a thin constantan or Nichrome wire, and let it ignite a piece of paper on a heat-proof mat. Don’t forget to discuss the energy changes in the burning paper.

Plenaries
Energy links – Get the students to draw a large circle with all of the forms of energy listed around the outside. They must then link the forms together with a sentence form each containing a device that can transfer the first form to the second. (10 minutes)
What’s the transfer? – Ask the students to describe simple energy transfers going on around the room, e.g. the ticking of a clock, the growth of a plant or the ringing of the bell marking the end of the lesson. (5 minutes)
One big energy transfer – Ask the students to draw a complete energy transfer diagram showing the transfers that have happened to produce the sound of them clapping hands, starting from the Sun: [Nuclear→light→chemical (in plants)→chemical (in humans)→ kinetic→sound→thermal]. (5 minutes)
Teaching suggestions
• Special needs. Provide a list of the forms of energy with examples. The students should add their own later.
• Gifted and talented. Are sound and thermal energy just forms of kinetic energy? Get the students to research and explain the links, then decide if we really need to use the terms ‘sound energy’ and ‘thermal energy’.
• Learning styles
Kinaesthetic: Manipulating objects in energy circus.
Visual: Making observations. Auditory: Explaining energy transfers in devices.
Interpersonal: Debating ways of describing energy.
Intrapersonal: Making deductions about energy transfers in energy circus.
• Teaching assistant. The teaching assistant can work with groups in the energy circus or follow a group that needs particular assistance.
• Homework. The students should make a list of the energy transfers that take place in devices at home.

Learning Outcomes
Most students should be able to:
• Describe in what form of energy is stored in fuels, hot objects and stretched objects.
• Draw simple energy transfer diagrams showing changes in energy.
Some students should also be able to:
• Describe, in detail, energy transfers involving gravitational, kinetic and thermal energy. Practical support
Demonstrating energy transfers
Throughout this unit, the students will see a range of energy transfers. You should challenge them to describe the transfers in each of them using only the recognised terms, avoiding common misconceptions like ‘steam energy’. Using many small demonstrations continually reminds the students that all transfers can be described fairly simply.
Energy circus
The students can carry out a range of simple experiments and describe the energy transfers involved. Some suggested objects/transfers are:
• A yo-yo. • A dynamo.
• A portable radio. • A hairdryer.
• A kettle. • An MP3 player.
• Dropping a steel ball bearing onto a wooden block.
•Burning a candle or fuel burner.
More difficult ones are:
• Citric acid solution and sodium hydrogencarbonate. This is an unusual endothermic reaction: can the students explain what is happening? [thermal→chemical]
• A remote-control car: what energy is reaching the car? [radio waves]
Activities and extensions
There is one further ‘form’ of energy: mass. The students can find out about the man who first realised that mass and energy are equivalent: Albert Einstein and his famous equation E=mc2. They could produce a presentation or poster explaining what this equation actually means.

AQA GCSE Science: P1a 2.2 What are the energy changes in a roller coaster?
AQA Specification Link
• Energy cannot be created or destroyed. It can only be transformed from one form to another form.
• When energy is transferred and/or transformed, only part of it may be usefully transferred or transformed.
Learning Objectives
Students should learn: • That energy is conserved in all energy transfers.

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
A plane journey – Ask the students to draw a cartoon of an aeroplane journey describing the changes in gravitational, kinetic and chemical energy. The aeroplane lands back at the same place it took off; ask them where the energy in the fuel has gone. (10 minutes)
Definition – What does the word ‘conservation’ mean? Ask the students to give examples of its use. (5 minutes)
Where does it all go? – Light a candle and ask the students to describe what happens to the chemical energy stored in the wax. (5–10 minutes)

Teacher Exposition pupil development
• The topic opens with a look at the transfer of gravitational potential energy to kinetic and back again. This is a common theme in examinations and time should be taken discussing the aspect with plenty of examples.
• Point out that energy is wasted during each transfer, so a roller coaster can never get as high as it first starts out.
• The law of conservation of energy is a very important one and must be emphasised strongly.
• The practical activities may take a bit of time to set up and are fiddly. The students should be thinking about how to improve the accuracy and reliability of the measurements (related to ‘How Science Works’) but it is unlikely they will think of using the shadow idea on their own.
• Use a web cam to record the pendulum swinging or you can record a video clip of the pendulum shadow in advance and show it during the lesson. If you project this onto a whiteboard, you can mark the heights of the swings as they happen.
• Watch and discuss a video of a bungee jump. Find one at www.video.google.com.
• An animation, P1a 2.2 ‘Conserving energy: the pendulum’ is available on the GCSE Science CD.
• In most situations, where a system seems to be losing energy, this can be explained by frictional losses producing heat. This is true for both the pendulum and the bungee.
• Check that the students can explain what is causing loss of energy in these systems.
• You can demonstrate that the loss is caused by air resistance by attaching a piece of stiff card to the bob and increasing its drag. This reduces the swing rapidly.
• You can demonstrate the bungee example using a mass on a spring or, more excitingly, with a toy on a length of fishing elastic.
• You may be able to find designs for perpetual motion machines on the Internet along with descriptions of how these may work.

Plenaries
Make up your own example – Get the students to make up their own example of conservation of energy listing where they think the energy goes. (10 minutes)
Conservation acrostic – Students write a short poem about energy based on the letters in the word ‘conservation’. (5–10 minutes)
Measuring the energy in food – Ask the students to design a simple experiment to measure the energy in a food sample. They should minimise energy loss to the surroundings. (10 minutes)

Teaching suggestions
• Special needs. Provide partly completed energy transfer diagrams to save time. The students still need to identify the missing energy forms or the device that performs the transfer.
• Learning styles
Kinaesthetic: Manipulating the pendulum and ‘bungee’.
Visual: Imagining the flow of energy from object to object. Auditory: Discussing energy loss in transfers. Interpersonal: Discussing experimental observations. Intrapersonal: Appreciating that energy is not ‘lost’.
• ICT link-up. Use video capture equipment to record the pendulum or ‘bungee’ for analysis. Some software can calculate speed and displacement.
• Science @ work. Roller coasters are so called because the cars just roll. They are lifted to a great height and then roll along the track without any external power; relying just on the transfer of gravitational energy to kinetic energy and back again. An exciting roller coaster takes a lot of scientific thought to design but not a lot to enjoy.

Learning Outcomes
Most students should be able to:
• State that energy cannot be created or destroyed.
• Describe energy transfers between gravitational, kinetic and elastic (strain) energy.

Some students should also be able to:
• Describe, in detail, energy transfers involving gravitational, kinetic and strain energy taking into account thermal energy.
Practical support
Pendulum swinging
Equipment and materials required
For each group: retort stand, string with bob (or 50 g mass tied to end), graph paper and some Blu-Tack to mount it, lamp.
Details
One way to measure the height of a pendulum swing is to shine a bright light onto it and measure the position of the shadow. Position the light so that the shadow falls on a piece of graph paper when the bob is swinging. The students mark where the shadow falls after a number of swings and then look at the pattern in height against time.
Bungee jumping
Equipment and materials required
For each group: retort stand, elastic with mass (or toy tied to end), graph paper and some Blu-Tack to mount it, lamp.
Details
A similar shadow technique to the above activity can be used to measure the height of the bounces.

Activities and extensions
• Although perpetual motion devices are impossible to construct, a number of people have tried. The students could research these devices and may even come up with an explanation of why they did not work.
• Sometimes we want to get rid of kinetic energy quickly. Students could find out how we slow down planes on landing, or drag racers, and make a booklet or short presentation (this would be good for homework).

AQA GCSE Science: P1a 2.3 Useful energy
AQA Specification Link
• When energy is transferred and/or transformed only part of it may be usefully transferred/transformed.
• Energy which is not transferred/transformed in a useful way is ‘wasted’.
• Both wasted energy and the energy which is usefully transferred/transformed are eventually transferred to their surroundings, which become warmer.
• Energy becomes increasingly spread out and becomes increasingly more difficult to use for further energy transformations.
Learning Objectives
Students should learn: • That thermal energy is lost to the surroundings in energy transfers.
• That this ‘wasted’ thermal energy is no longer of use.
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Useful or useless? – Show energy transfer diagrams and ask the students to identify the useful energy outputs and the useless ones in each case. Try some trick ones. (5–10 minutes)
Friction revision – Why do snooker balls stop rolling after being hit? Get the students to describe the ways that the initial kinetic energy is lost. (5 minutes)
Overheating – Ask students to explain why humans become hot when they work hard. How is this excess heat removed from the body? Why do we need to eat less in hot weather? (10 minutes)

Teacher Exposition pupil development
• In this unit avoid the use of the terms ‘lost’ for energy if possible; it implies that the energy disappears. The energy spreads into the surroundings and becomes useless or ‘wasted’.
• A video clip of a car performing an emergency stop is an excellent way of getting the students to understand that the kinetic energy of a car has to go somewhere when it stops. A dramatic one with burning rubber works best. Try www.video.google.com and search ‘car crash barrier’ or’car crash kings’ for stopping very quickly!
• The technology department should have an electric drill and some scrap wood. With poor drilling technique (don’t push into the wood; instead allow the bit to rub the sides) you should be able to get some smoke to show the heating effect. Sneakily putting a dab of oil on the drill bit seems to help too.
• Frictional effects are best explained using simple diagrams or animations. The surfaces rub or catch on each other and this rubbing causes heating. You can show the roughness of ‘smooth’ surfaces with micrographs or even electron micrographs.
• Rubbing two metal blocks across each other will show frictional heating. Adding oil should make the movement smoother.
• Check that the students understand that friction causes heating because of the forces between the surfaces of objects rubbing together.
• The students need to be encouraged to describe exactly where there is friction in a device. They should know about air resistance, drag in water, friction of surfaces in contact and around a pivot.
• If you have an exercise bicycle in the school, then this can be used to show the heating effect on the brake blocks. You could also put oil on the blocks to show that this reduces the friction and makes it harder to stop the wheel turning. An animation, P1a 2.3 ‘Disk brakes on a car’ is available on the GCSE Science CD.

Plenaries
What’s wrong? – Ask the students to correct this sentence ‘When a car stops at traffic lights, the speed energy is destroyed by the brakes and is lost’ [or similar]. (5 minutes)
Removing the heat – A car engine has many moving parts and produces a lot of heat. Get the students to describe how the friction is reduced and to think back and describe how that wasted energy is transferred to the surroundings. (10 minutes)

Teaching suggestions
• Gifted and talented. What really causes frictional forces? Very smooth surfaces often produce larger frictional effects than rougher ones. Can the students come up with a detailed explanation of what is going on?
• Learning styles
Kinaesthetic: Practical tasks. Visual: Observing frictional effects and recording experimental data. Auditory: Explaining the cause of friction.
Interpersonal: Evaluating experimental technique. Intrapersonal: Evaluating experimental technique.
• Homework
• The students can find details about surfaces. They should be able to find the most slippery surface in the world and possibly close-up pictures of different surfaces.
• They could list other devices and decide on the useful and wasted energy.

Learning Outcomes
Most students should be able to:
• Identify useful and wasted energy in transfers.
• Describe how friction is the cause of much wasted energy.
• Understand that energy that escapes to the surrounding as heat is not available for other energy transfers and so is useless.

Practical support
Investigating friction
Many students will have looked into friction before, but you may wish to look in more detail here. The focus should be on improving the technique focusing on the accuracy and precision concepts of the specification (this relates to ‘How Science Works’).
Equipment and materials required
For each group: string, pulley, clamp, 10_50g masses, 1 kg mass (with hoop), three different surfaces to test (desk surface, carpet tiles, rubber mat).
Details
The students place the 1 kg mass on the surfaces and attach it to a mass holder hanging over the desk via the pulley. The students then find out what mass is required to start the 1kg sliding across the surface. To improve the accuracy of the measurements, encourage them to add smaller masses when they get near to the sliding point of the mass, so several runs will be required. The students may find out that their mats or carpet tiles start to move before the mass, so will need some tape or Blu-Tack to hold it in place. How does this work?
Safety: Protect floor from falling weights and keep feet clear.

Activities and extensions
It took scientists some time to come up with ideas about thermal energy, friction and work. The students could look into the concepts of ‘phlogiston’ and then ‘caloric’ to explain heating effects. These are fairly complex ideas; the students need to be careful that they don’t confuse them with the more modern concept of thermal energy.

AQA GCSE Science: P1a 2.4 Energy and efficiency
AQA Specification Link
• The greater the percentage of the energy that is usefully transformed in a device, the more efficient the device is.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to calculate the efficiency of a device using:
Efficiency = useful energy transferred by the device total energy supplied to the device

• to evaluate the effectiveness and cost effectiveness of methods used to reduce energy consumption.
Learning Objectives
Students should learn: • How to measure the efficiency of a motor.
• How to calculate the efficiency of a range of devices.

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Efficiency – What is ‘efficiency’ and why do we want it? What are the advantages of an efficient device? (5 minutes)
Staying on – Ask the students to explain why some electrical devices last longer than others even though they use the same batteries. (5 minutes)

Main
• This may be the first time the students will have encountered an equation in the course; time should be spent ensuring that they get it right.
• They need to lay out the calculations clearly and show all of the stages of their working; emphasise that they will find it difficult to remember the correct technique and score full marks on a science examination without doing this.
• Investigating the efficiency of the winch may be difficult without a lot of equipment. Demonstration only
• Allow the students to record the results and produce a line graph. They should find that the motor becomes less efficient as the mass increases. This introduces concepts of ‘How Science Works’ involving presentation of data and relationships between variables.
• Ask them why they think the efficiency becomes less. [The main reason is that frictional forces in the motor increase but there is some extra air resistance that they may mention.]
• You may like to discuss how the efficiency of an elevator could be measured. Should the weight of the elevator itself be counted? This could lead onto a discussion of why it is not efficient (or cost effective) to drive a large car with only one person in it.
• Many students may own personal music players (MP3 players) or mobile phones, some of which have a much better battery life than others. These can form the basis of a discussion about the advantages of an efficient device.
• The calculations are not particularly challenging, but many students become confused about percentage or fractional efficiency.
• It is usually best to stick to the fractional efficiency, as this is commonly used in examinations and makes the equation easier to handle and rearrange.
• You should check through the answers with the students before the plenary.

Plenaries
‘The lads gave it 110%!’ – Get the students to explain what’s wrong with that statement. Can you put in more than 100% effort? (5 minutes)
Car efficiency – Give the students advertisements for cars and ask them to arrange them in order of energy efficiency, using the fuel consumption figures in the small print. Is a bus more energy efficient than a car? (5 minutes)
Energy efficiency poster – Students can draw a poster encouraging people to be more energy efficient in their home. (10 minutes) after feedback complete for H/W

Teaching suggestions
• Special needs. Allow the students to use an experiment template with clear instructions and a results’ table during the practical task.
• Learning styles
Kinaesthetic: Setting up the apparatus.
Visual: Obtaining accurate measurements.
Auditory: Explaining the cause of friction.
Interpersonal: Collaborating with others in practical work. Intrapersonal: Reviewing and evaluating results.
• Homework. A worksheet with additional calculations would be appropriate. You could provide data from the lifting experiment for the students to analyse if they did not try the task during the lesson.
• Teaching assistant. Have the teaching assistant help out with the practical and support those who have difficulty plotting graphs.

Learning Outcomes
Most students should be able to:
• Calculate the efficiency of a device.

Some students should also be able to:
• Perform calculations including the rearrangement of the efficiency equation.

Practical support
Investigating efficiency
This investigation can be used to develop and assess the students’ investigative skills, in particular those related to measurement. If you do not have enough joule meters it is possible, but trickier, to use an ammeter, voltmeter and stopwatch combination using the equations below to calculate energy use.
Equipment and materials required
For each group: joule meter, variable power supply, small electric winch (motor), 5 x 100g masses (each weighing 0.1 N), metre rule, clamps to secure the winches to benches.
Details
• The students will lift a range of masses a fixed height. A full metre is a good height, if the motor were 100% efficient it would require 0.1 J for each mass. In reality it will be much less efficient than this. If the winches are quite powerful, you may need to use larger masses to notice the reduction in efficiency.
• Some students may want to know how the joule meter measures energy. It calculates energy provided by measuring the current and potential difference across the motor. The energy used is then calculated using: energy = current x potential difference x time (E=Pt and P=IV ). The students will meet these equations later in the course.
Safety: Protect floor and keep feet clear from falling weights.
Activities and extensions
The students can research into car efficiency. A large amount of information is available about the performance of a car; the students can find this and produce a graph showing which is the most fuel efficient. Several groups could look into different classes of car to find the ‘best in class’ and share their findings.

AQA GCSE Science: P1a 2.5 Energy and efficiency issues
AQA GCSE Science: P1a 2.5 Energy and efficiency issues (OPTINAL EXTRA LESSON IF TIME!)
AQA Specification Link
Substantive content that can be revisited in this spread:
• Energy cannot be created or destroyed. It can only be transformed from one form to another form.
• When energy is transferred and/or transformed only part of it may be usefully transferred/transformed.
• Energy that is not transferred/ transformed in a useful way is ‘wasted’.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to evaluate the effectiveness and cost effectiveness of methods used to reduce energy consumption.
Teaching suggestions
Activities
Ideas about energy – Provide each group with a large sheet of paper to express their ideas. As individuals, they could then produce an energy saving manifesto booklet, perhaps as homework.
The bouncy ball test – The students can investigate the bouncing of balls on hard surfaces. Squash and ping-pong balls are a good choice for most surfaces and golf balls work well on very hard floors. A ball from a computer mouse does not bounce well; see if the students can suggest why.
Equipment and materials required
For each group: metre rule, various balls.
A burning issue – As before, the students’ reports can be recorded on video or with a digital camera or web cam. Alternatively, if you recorded some discussions from the start of the first chapter you might like to show them now as a starter to the debates.
Extension or homework
Research – Quite a lot of information is available about James Joule so the students could easily be set a homework task of researching his achievements. Did he really spend his honeymoon measuring the temperature of water beneath a waterfall or is this just a scientists’ urban myth? An animation, P1a 2.5 ‘Joule’s experiment’ is available on the GCSE Science CD.
Additional calculations – The students could complete several calculations from a worksheet on efficiency.
Learning styles
Kinaesthetic: Practical work with bouncy balls.
Visual: Watching video reports.
Auditory: Discussing efficiency issues.
Interpersonal: Debating the site of an incinerator.
Intrapersonal: Evaluating the usefulness of hybrid cars.
Special needs
Use a worksheet with partially completed calculations to teach the students how to lay out calculations.
Gifted and talented
These students could look into the topic of elastic and inelastic collisions using dynamics trolleys, perhaps using light gates to monitor the motion. They can find out which type of collision cause the greatest changes in energy.
Teaching assistant
Your teaching assistant can be very helpful in the recording of discussions or helping to generate ideas in group work.
ICT link-up
• Students can find information on the Internet about the latest hybrid car technology. See for example, www.hybridcars.com or try the various car brand name web sites.

AQA GCSE Science: P1a 3.1 Electrical devices
AQA Specification Link
• Examples of energy transformations everyday electrical devices are designed to bring about.
• Examples of everyday electrical devices designed to bring about particular energy transformations.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different electrical devices for a particular application.
Learning Objectives
Students should learn:
• That electrical devices are very useful.
• About a range of energy transformations that happen in electrical devices. Teaching / Learning activities (including How Science Works)
Lesson structure
Starter
Show the picture of a kitchen from E science page 254 (similar to one in the book page 254) – ask pupils to list 5 electrical devices, their useful energy and wasted energy (can be put into table form)

Teacher Exposition:
• The core part of this topic is a discussion of why electricity is so useful in our society and the main energy transfers involved:
• The students will easily appreciate that electricity can be transformed into other forms of energy easily, so spend some time mentioning and showing the key devices that do the job.
• Show a wire heating when a current passes through it and ask students what this effect is used in.
• Use a heat-resistant mat and turn up the current until the wire becomes white hot (for a moment). Students need to be out of touching distance.
• Ask the students: ‘What is this effect used in and how do we make sure that the wire does not melt?’
• Show an electric motor operating, pointing out the magnets, and ask how this effect is used. Also ask: ‘What is the effect of increasing the current and providing more energy to the motor?’
• Demonstrate a simple electromagnet and again see if the students realise how this effect can be used in loudspeakers (have one handy with a signal generator).
• With each of the demonstrations, ask the students to consider how energy is being wasted to the surroundings.
• Once the students are aware of the range of possible transfers, they should discuss how to choose a particular device for a job.

Pupil Development:
Get the pupils to compare the table from page 254 with the starter
Pupils work through the spread and answer the summery questions on page 255

Plenaries
No electricity – The students should write a description of the problems they would have during the morning if there were no electricity. Or
Electrical energy table – Give the students a cut-up table similar to the one in the textbook and ask them to assemble it to show the useful and wasted energy from more electrical devices. (5 minutes)
Teaching suggestions
• Gifted and talented. These students could find out who first discovered how electricity could be used to produce movement. How and where was this first demonstrated? Was its importance realised?
• Learning styles
Kinaesthetic: Cutting and pasting activity. (See plenaries.)
Visual: Creating a mind map. Auditory: Discussing the right appliance for the right job. Interpersonal: Discussing the operation of electrical devices. Intrapersonal: Considering wasted energy in demonstrations.
• Homework
• The students could find out where all the electrical effects demonstrated today are used in industry or around the school.
• The ‘no electricity’ plenary could be used as the topic of a longer story that the students could write if not used during the lesson.

• Science @ work. The clockwork radio isn’t the only device that can be used in locations without many resources. There are several clockwork torches that use the same principle. There is another design where you just shake the torch to charge it. This shaking makes a magnet move between coils of wire and generates a small electric current. It’s handy if you are going to be trapped in a cave for a long time. Learning Outcomes
Most students should be able to:
• Describe the energy transformations in a range of electrical devices.
• Choose a particular device for a particular purpose based on the energy transfer required.

Practical support
Demonstrating heating effect of electrical current
Materials and equipment needed
Low voltage power supply (variable), resistance wire, heat proof mat.
Demonstrating a motor
Ideally you should use a motor where the students can see the moving parts. This way you can describe the effect the current is having.
Demonstrating a loudspeaker
The loudspeaker should be a large one, and you should demonstrate that all it is doing is moving in and out by showing some low frequency vibrations.
Activities and extensions
How long will the resources last? – The students will be aware of the limits of fossil fuel resources, but perhaps not in the uncertainty of the figures which have remained roughly the same for the last 30 years. Ask them to find out about recent discoveries of new oil reserves and how these affect the predictions. They could debate the political and social problems caused by these new found resources.

AQA GCSE Science: P1a 3.2 Electrical power
AQA Specification Link
• The amount of electrical energy a device transforms depends on how long the appliance is switched on and the rate at which the device transforms energy.
• The power of an appliance is measured in watts (W) or kilowatts (kW).
Learning Objectives
Students should learn:
• That the power rating of a device is a measure of how much energy it transfers each second.
• How to calculate the power of a device.

Some students:
That high powered devices use more energy Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Power – Ask the students to describe what they mean by the word ‘power’. Ask: ‘Who is the most powerful person in the world, what is the most powerful machine?’ (5 minutes)
Big numbers – Give the students a set of SI prefixes and see if they can be placed in order of size.
(5 minutes)

Teacher exposition
• Begin with a discussion of power and the clear scientific definition as ‘the amount of energy transferred each second’.
• If you feel brave you may like to try a real physics joke, ask the students: ‘Watt is the unit of power?’ like a question. When they say that they don’t know, then do it again!
Make them familiar with the equation power = energy transferred / time take
• The unit ‘watt’ is exactly the same as ‘a joule per second’ and this is a common concept tested on examinations.- emphasise all the units
• Some students seem to struggle with the term ‘per’ and you may like to explain this as meaning ‘each’.
• Emphasise that the prefix ‘kilo’ just means ‘one thousand’. Check that the students can understand numbers like 2.4kW and 0.5kW, as some have difficulty; if they are struggling it is sometimes best to say the ‘kilo’ means ‘multiply the number by one thousand’.
• Similarly, some students will need the prefix ‘mega’ explained to them carefully.
• Plenty of example calculations are required and the students need to develop a clear layout of these.
• A rigorous method should be stuck to, and you should check that the students are getting the correct answers with their method.
Discuss the different power ratings from the Argos catalogue and elicit the devices that are high powered tend to heat and are more expensive to run

Pupil development
Pupils write down the equation and have a go at the example on page 256
Issue Argos catalogues to pupils and ask to find the power ratings of 5 different electrical devices
Pupils complete summery questions from page 257

Plenaries
Matching the power – Give the students a set of pictures of household electrical devices and a set of power ratings. Ask them to match the ratings with the devices (take from the Argos cat while they do the Argos Task)

Item Power (W)
Microwave 800
TV 150
Electric fire 2000
Electrical drill 150
Light bulb 60

Teaching suggestions
• Special needs. You may need to provide a layout template for the calculations for some students to develop the skills. These may contain partly completed equations.
• Gifted and talented. The power output of our Sun, a typical star, is much greater than the power needed for everybody on the Earth. How could we harness this power to meet our energy demands for the next billion years? The students could look into such exotic solutions, such as space mirrors, ring worlds and Dyson Spheres. The outcome could be a dramatic presentation of the far future.
• Learning styles
Visual: Imagining the scale of the power output of the Sun.
Auditory: Definitions of key words and units.
Interpersonal: Discussing the meaning of ‘power’.
• Homework. Further calculations may be useful. The students could look into the origin of the term ‘horsepower’ and find out how many watts one horse power is.

Learning Outcomes
Most students should be able to:
• State that the watt is the unit of power.
• Calculate the power output of devices using the equation:

Power =energy transformed time

Some students should also be able to:
• Pupils predict the power of a range of electrical devices

Activities and extensions
Equipment and materials needed
Argos Catalogues – class set

AQA GCSE Science: P1a 3..3 Using electrical energy
AQA Specification Link
• The power of an appliance is measured in watts (W) or kilowatts (kW).
• Energy is normally measured in joules (J). Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to calculate the amount of energy transferred from the mains using:

energy transferred = power x time
(kilowatt-hour) (kilowatt) (hour)

• to calculate the cost of energy transferred from the mains using:
Total cost = number of kilowatt-hours x cost per kilowatt-hour

Learning Objectives
Students should learn: • How to calculate the energy transferred by mains supplied electrical devices.
• How to calculate the cost of operating electrical devices.

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
How much? – Give the students a set of devices and the time they are used for (e.g. a TV for 4 hours). They must put them in operating cost order. (5 minutes) Item Power (W) Number of Hrs used per day (hrs)
Microwave 800 0.25
TV 150 4
Electric fire 2000 0.5
Electrical drill 150 .05
Light bulb 60 4

Teacher exposition
Demo the Joule meter and use with the different electrical devices
• This is another quite mathematical concept with important calculations, but the most common difficulty is the name of the units.
• The students really need to understand that a ‘kilowatt-hour’ is a measure of an amount of energy, so spend some time going through this.
• Converting between kilowatt-hours and joules is quite common in examinations and this must form part of the discussion. –
KWh is a unit of energy (W=J/s)
1 KWh – 3.6MJ
1 unit on the bill = 1KWh
• The terms ‘kilowatt hour’ and ‘unit’ are often interchanged and the students need to be aware of both.
• Make sure that the students can work out how many units have been used when given two different meter readings.
• Some students struggle when talking about immaterial things like ‘units’, and you may need to give analogies like ‘how many gobstoppers could you buy for £2 if they cost 7p each’ and so on.
• Higher attaining students should work out how many units could be bought with a set amount of money.

Student development
Pupils run through the spread and do summery questions on page 259

Plenaries
Big bill – Show the students a copy of the school electricity bill and ask them to think of ways they could reduce it. (10 minutes)
Choosing the best supplier – Give the students copies of two pricing structures: one with a standing charge, and one without a standing charge but with a higher price per unit. Ask the students to find out which company three different families should use. (10 minutes)
Calculation dominoes – Give groups a set of domino cards with questions and numerical answers. Let them play dominoes with them. (5–10 minutes)

Teaching suggestions
• Special needs. As before, a layout template for calculations will help a great deal.
• Gifted and talented. Can these students calculate the energy use from a 100 W bulb left running for a year, in joules?
• Learning styles
Kinaesthetic: Playing a game of dominoes.
Visual: Obtaining information from bills and meter readings.
Auditory: Debating how to reduce electricity costs.
Interpersonal: Discussing the benefits of saving energy. Intrapersonal: Interpreting information from an electricity bill.
• Homework. The students could check their own electricity bill and find out how much they are paying per unit. They could find out what each supply company is charging.

• ICT link-up. The students could use a simple spreadsheet to calculate the cost of the electricity used. They could then find out what would happen to the price if the cost per unit increased or decreased.

Learning Outcomes
Most students should be able to:
• Calculate the amount of energy used by a mains device (in kWh). Equipment
• Calculate the cost of the electricity used. Joule meter and electrical meter Variety of electrical devices
Some students should also be able to:
• Carry out rearrangement of the appropriate equations.

AQA GCSE Science: P1a 3.4 The national grid
AQA Specification Link
Electricity is transferred from power station to consumers along the National Grid.

Learning Objectives
Students should learn: • How the National Grid is used to transfer electricity around the country. Most
Explain the benefits/problems between overhead and underground cables

Some
Explain why high voltages are used to transport electricity long distances on the Nat Grid

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Where does electricity come from? – Ask the students to explain where the electricity to power the lights in your room actually comes from. Ask them what happens when the local power station is out of operation. (5 minutes)
Danger of death – Show the students a picture of the ‘Danger of death’ icon used on transformer sub-stations. Ask them what they think the danger is and what the icon is showing. You could also check the students’ knowledge of other hazard symbols. (5 minutes)

Teacher exposition
• Demo a demountable transformer and it function of stepping up/down an electric current/voltage

• Use this diagram to explain the voltages about how the electricity gets from the power station to your homes (this diagram found on work sheet used later in the lesson)
Show David’s demo of the transformer and pylons
Can show video ‘electric cty’

• If the students live close to a pylon they can describe how large they are and what they are made of.
• If a sample of aluminium cable is not available, then use sample blocks of aluminium and steel to compare the density of the two materials. The students will easily see the advantage of using aluminium.
• It also helps if the steel is a bit on the rusty side, so that you can show the aluminium is also easier to maintain.
• The underground/over ground discussion could be expanded; see ‘Activity and extension ideas’ box.

Pupil development:
Pupils complete worksheet P1a 3.4

Plenaries
NOT IN MY BACKYARD! – pupils vote for what sort of cables they would have in their area – be prepared to give one reason

Teaching suggestions
• Gifted and talented. These students could find out what a transformer is and how it operates. What is it made of and why does it have a laminated iron core?
• Learning styles
Kinaesthetic: Researching effect of pylons on health.
Visual: Viewing the structure of the National Grid.
Auditory: Explaining the reasons for carrying electricity at high voltage.
Interpersonal: Reporting on research.
Intrapersonal: Considering the effect of pylons on the landscape.
• Homework. If the students did not redesign the ‘danger of death’ symbol, they could do this on a larger scale at home. They could produce a booklet warning of the hazards of messing with electricity pylons.

Learning Outcomes
Most students should be able to:
• Explain the advantages of providing electricity via a National Grid.
• Describe the role of pylons, cables and transformers in the national Grid.

Some students should also be able to:
• Explain why electricity is transferred at very high voltage.

Practical support
DAVID’s - Demo high voltage energy transfer
To demonstrate that high voltages are more efficient at transferring electrical energy, the following method can be used. It is fiddly to get just right, so make sure that you have tested it first.
Equipment and materials needed
Two matched transformers with a step-up or step-down ratio of about five (e.g. 100 turns input and 500 turns output). Two 2m lengths of thin wire with high resistivity (Nichrome or constantan work well), a 1.25 V lamp and a low voltage (1–1.5 V) a.c. power supply.
Details
• Connect the power supply directly to the lamp through the long wires. The lamp should light dimly at best. This is because most of the energy is being wasted in heating the wires. Don’t leave this set up on for long or the wires could overheat.
• Next connect the wires to the step-up transformer at the power supply end and the step-down transformer at the lamp end. The voltage in the wires will increase by a factor of five and the current will be reduced by a similar amount. This will lead to a twenty-fifth of the heating effect and energy wastage so the lamp should be much brighter.
• To make the demonstration more like the National Grid, you could suspend the wires on retort stands.

Demo
Demountable transformer

Similar Blocks of Al and Steel (one rusty)
Class set of P1a 3.4

Activities and extensions
Do pylons affect our health? –
Some groups believe that the electromagnetic fields produced by electrical cables seriously affect our health. The students can try to find out if there is any evidence supporting this position. It is important that the students understand the nature and quality of the evidence presented to them, so they can judge the validity of any conclusions drawn (this relates to ‘How Science Works’).This can lead to a discussion about the nature of anecdotal evidence.
Choosing the right cables –
There are a number of reasons for choosing which method and there is plenty of information available about how the decisions are made. The students could be given a scenario (or several) and choose which method to use to transfer electricity. The National Grid has its own web site, which is a good place to start the research.

AQA GCSE Science: P1a 3.5 Essential electrical issues OPTIONAL LESSON only if TIME!
AQA Specification Link
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to calculate the cost of energy transferred from the mains using:
Total cost = number of kilowatt-hours x cost per kilowatt-hour

Teaching suggestions
Activities
Plugs – Why have different countries and different appliances got different plug designs? The students can research the designs for different countries and find out why some countries only have two pins. Why do some devices only need two wires instead of three?
Extension or homework
Even better plugs – Can the students design a better plug? They should design the shape and the materials, explaining these choices. Which parts should be conductors, which should be insulators? Why is the Earth pin slightly longer than the other two on a UK plug?
More about mains – The UK mains supply is 230 V alternating current. The students could find out why these decisions were taken. Ask: ‘What does “alternating current” mean and what is it that causes it to change with a frequency of 50 Hz?’ ‘Why have the Americans got a system of 115 V at 60 Hz?’
Nikolai Tesla – Nikolai was a prolific inventor and excellent engineer. Although his broadcast power technology did not catch on, there are a large number of devices still in use that he invented. The students can find out what these devices are and how they affect their lives.
Lighting without electricity – Gas lamps and candle lamps are dim. Can the students find a way of making the flames brighter? Can they design a gas-lit torch where the light can be directed? This may involve a design that guides more oxygen to the flame or uses lenses to focus the beam.
Learning styles
Kinaesthetic: Designing new plugs.
Visual: Thinking up a new invention.
Auditory: Reading information aloud.
Interpersonal: Discussing different mains systems.
Intrapersonal: Deducing problems.

Special needs
New football kits
How can football kits be redesigned to make them more visible to people with sight problems? Show some sample materials and discuss which would be the best for the teams to wear. Do some work under floodlights better than others? The students could design a test. Referees usually wear black, but should they change to white?
Gifted and talented
The problems with broadcast power
The fact that anybody can receive it is not the only problem with broadcast power systems. What other problems can the students think of? Are radio waves damaging to the body? What happens to the energy from the waves that are not received?

AQA GCSE Science: P1a 4.1 Fuel for electricity
AQA Specification Link
• In most power stations an energy source is used to heat water. The steam produced drives a turbine which is coupled to an electrical generator.
• Common energy sources include coal, oil and gas, which are burnt to produce heat and uranium/plutonium, in which nuclear fission produces heat.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different energy sources to generate electricity.
Learning Objectives
Students should learn: • How a fossil fuel based power station operates.
• The differences between using fossil fuels and nuclear fuels in electricity generation.

Most
Compare that more energy is released from kg of uranium than fossil fuel
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Nuclear power – what do students know about nuclear materials? List their ideas and try to iron out some misconceptions.

Teacher exposition
• Start by demonstrating the combustion of some fuel. This could be a simple Bunsen flame -Discuss energy being released during oxidation of carbon.
• You could put a conical flask of water above the flame and let it boil. Add a bung with a pipe to show steam generation and demonstrate with a windmill for the turbine. – at same time set up the steam engine and demo how it can generate electricity.
• Link these ideas to electricity generation; an animation of the processes involved in a power station gets the stages across clearly. Emphasise the difference in scale and the high pressure and temperature of the steam in a power station. – science page 266 has a good diagram as in the book and MMScience school NAME also shows in section how a power station works and Escience has good interactive diagram from page 267
• The students need to be able to state what each part of the power station does, so it is best to go through them thoroughly and check understanding at each stage.
• Relate diagrams back to earlier demonstration of a turbine – discussing the different fossil fuels used to generate heat and electrical energy.
.Show the video clip (5mins long) from escience page 266 – Generating electricity the non–renewable way
Run through the spread on page 266/7
Discuss formation of electricity via a nuclear power station and for the same weight nuclear fuel produces much more energy than fossil fuel
• The students should be reasonably familiar with the parts of an atom and need to focus on the nucleus.

Pupil development
Pupils write down the energy changes involved with a power station
Pupils work through the spread
Pupils summarise the differences between nuclear and fossil fuels

Plenaries
Not in my back yard – if you had to which would you have near to your house a nuclear or a coal fired power station-give two reasons for your choice Teaching suggestions
• Special needs. Students could be provided with a diagram of a power station and complete the labelling of the important components.
• Gifted and talented. If atoms are too small to see, how do we know what they are made of? The students should find out how the nuclear model of the atom was discovered.
• Learning styles
Kinaesthetic: Researching information.
Visual: Observing demonstrations. Auditory: Discussing nuclear power.
Interpersonal: Reporting on waste disposal.
Intrapersonal: Evaluating advantages and disadvantages of nuclear power in comparison to fossil fuels.
• ICT link-up. Many of the energy generating companies have web sites with information about power stations. Students can explore these to get a better idea of what is going on.

Learning Outcomes
Most students should be able to:
• Draw a flow chart showing the stages of electricity generation in a power station.
• Describe the similarities and differences between different power stations.

Some students should also be able to:
• Evaluate the advantages and disadvantages of nuclear power in comparison to fossil fuels.

Practical support
Demonstrating the steam engine to make electricity;
Steam engine and safety screens
Generator with bulb
Band to run from fly wheel to generator (if you have not used it try it first!)
Conical flask
Bung and tubing with a right angled bend
A child’s wind mill

SAFETY
Steam engine gets very hot and use safety screens
Activities and extensions
Is nuclear power the future? – Many countries are developing nuclear programmes to generate electricity, but is this the way forward? These are clear advantages and disadvantages between nuclear power and fossil fuels, so the students could produce a booklet allowing people to vote on which of the two methods should be developed further in the UK. The booklet should contain all of the facts from both sides of the argument and a detachable voting slip.
Waste – Ask students to come up with plans for the disposal of nuclear waste. They need to think up ideas to keep it safe, cool and easily identifiable for thousands of years. Perhaps they can research information about how it is stored now. Some might think that blasting it into space is a good idea, but they should be encouraged to think of the problems involved with this.

AQA GCSE Science: P1a 4.2 Energy from wind and water
AQA Specification Link
• Energy from renewable energy sources can be used to drive turbines directly.
• Renewable energy sources used in this way include wind, the rise and fall of water due to waves and tides, and the falling of water in hydroelectric schemes.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different energy sources to generate electricity.
Learning Objectives
Students should learn: • How wind turbines can be used to generate electricity.
• How water can be used to generate electricity in a variety of ways.

most
• The advantages and disadvantages of the above methods of electricity generation.
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Water cycle recap – The students should draw a diagram explaining the water cycle. (10 minutes)
Tides and the Moon – Can the students explain how the Moon (and the Sun) cause tides? (5 minutes)

Teacher exposition
• You may want to show the students the ideas behind a turbine and generator. Although you won’t be able to light up a bulb with wind power, you can demonstrate the principle with a hand-turned generator..
• A video clip of a wind farm in operation gives a good idea of the scale of these structures and may also show the noise. Search for ‘wind farm’ at www.video.google.com.
Use MMscience in physics ‘power production’- school to show how different renewable energies work to generate electricity or
• An Interactive, P1a 4.2 ‘Alternative power production’ is great to shoe renewable energy sources on Escience
• There are several alternative designs for wave-powered generators; you could ask the students how they think they work.
• The idea behind a hydroelectric scheme can be shown simply by letting water flow down a pipe from a raised reservoir. This can be directed onto a paddle wheel causing it to spin.
• You may want to show students accelerated video clips of a tide coming in or out, as they may not have seen the effect before.www.video.google.com – search ‘time lapse tides’
• Compare and contrast advantages/disadvantages of the energy sources covered in this lesson as a class discussion.
(can show Escience video Generating electricity the ecological way clip (5 mins) about burning chicken poo as another alternative to fossil fuels)
Pupil development
Summery questions on page 269

Plenaries
Designing a tidal barrier – The students should design a tidal barrier that generates electricity, allows traffic to cross the river, and lets boats through when necessary. (10 minutes)

Teaching suggestions
• Gifted and talented. Can the students design, and explain, a new form of wave power generator?
• Learning styles
Kinaesthetic: Making a poster. Visual: Drawing an advertisement. Auditory: Explaining the benefits/ problems of renewable energy. Interpersonal: Debating the use of tidal barrages. Intrapersonal: Evaluating the impact on the environment.
• Homework. The students should be able to find out the location of the UK wind farms and find out why they were placed in these locations; can the students design a more attractive wind turbine?

Learning Outcomes
Most students should be able to:
• Describe how wind turbines generate electricity.
• Describe the different ways in which the flow of water can generate electricity.

Some students should also be able to:
• List some advantages and disadvantages of these methods of electricity generation.
• Evaluate the advantages and disadvantages of the methods of electricity generation.

Practical support Activities and extensions
Why not build a tidal barrage across the Severn or the Mersey? These rivers are ideal for generating lots of electrical energy, but what are the problems involved? Get the students to debate the issue and find out all of the potential problems.

AQA GCSE Science: P1a 4.3 Power from the sun and the earth
AQA Specification Link
• Electricity can be produced directly from the Sun’s radiation using solar cells.
• In some volcanic areas hot water and steam rise to the surface. The steam can be tapped and used to drive turbines. This is known as ‘geothermal energy’.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different energy sources to generate electricity.
Learning Objectives
Students should learn:
• How solar cells can be used to generate electricity at high cost and in relatively small amounts.
• How geothermal energy can be used to generate electricity in a variety of ways. most • The advantages and disadvantages of the above methods of electricity generation.
Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Rock cycle recap – The students should draw a simple diagram showing the rock cycle and naming all of the rock types. (5–10 minutes)
Old faithful – Show a video clip of Old Faithful (search for ‘Old Faithful’ at www.video.google.com ). Ask students if they have ever seen a geyser and if they know what causes them. (5 minutes)
Don’t anger the volcano god! – Ancient civilisations believed that volcanic eruptions were caused when Gods became angered. What is the scientific explanation? (5 minutes)

Main
• Demonstrate a solar cell being used to turn a small fan; you may need a bright lamp to do this.
• If you have a data projector and are using this during the lesson, it is also a great light source for demonstrating solar cells on a dreary day. You can even show that some solar cells work better in different coloured light; just use coloured backgrounds to blank slides.
• You can show how inefficient the cells are by using a very bright light shining on a panel that is lighting up a small bulb.
• If students are not investigating how the amount of light falling on the cell affects the output, they can simply show this idea by moving the cell further from the lamp; the small bulb should grow visibly dimmer. Students can develop concepts of ‘How Science Works’ by considering how to gather quantitative data when investigating solar cells.
• Small solar-powered garden lights are available from garden centres quite cheaply. Charge one of these up during the day and then cover the light sensor during the lesson, to show that it has been charged by collecting energy from the Sun. Link this to the idea of using a battery to store the energy for night time’s use which increases the expense.
• You may like to try to demonstrate the solar heating technique described in ‘Practical support’.
• Show some images of solar cells used on satellites and discuss why they are an ideal solution for electricity generation in space.
• Demonstrating geothermal energy is not easy, so use video clips and diagrams to get the ideas across.
• The focus should be on understanding that the energy comes from radioactive materials.

Plenaries
Solar car – Show pupils the picture of a solar car(for a solar car in action go to www.video.google.com and search for solar car). Ask them to list the advantages and disadvantages of the design. (5–10 minutes)

Teaching suggestions
• Gifted and talented. These students could find out how a solar cell actually works. This is quite a complex process but some may be up to it.
• Learning styles
Kinaesthetic: Carrying out experiments.
Visual: Observing the operation of solar cells and panels.
Auditory: Discussing the effectiveness of solar cells. Interpersonal: Reporting on the location of geothermal power stations.
Intrapersonal: Understanding how geothermal power stations work.
• Homework. As a research project, the students can find out where the best places to site geothermal power plants and solar power plants are. They should be reminded that the plants shouldn’t be too far from civilisation.
• Teaching assistant. A teaching assistant will be of great help during the investigations or operating the solar heater.

Learning Outcomes
Most students should be able to:
• Describe how a solar cell can be used to produce electricity.
• Describe the different ways in which geothermal energy can generate electricity.

Some students should also be able to:
• List some advantages and disadvantages of these methods of electricity generation.
• Evaluate the advantages and disadvantages of these methods of electricity generation.

Practical support
Solar cells
A solar cell can be demonstrated with a low-power electric motor.
Equipment and materials required
Solar cell, motor and lamp.
Details
A low-power motor will be required; complete kits containing a matched solar panel and motor are available. The students should be able to discover that the motor will turn faster the closer the lamp is to the cell. They might like to compare the speed of the motor in bright sunlight to that produced by a lamp.
Demonstrating solar heating
It is possible to show solar heating using sunlight or a bright lamp.
Equipment and materials required
Cold water tank and warmed water tank, two temperature sensors attached to a data logger, a pipe clamp, and a large metal plate sprayed matt black with a long thin tube mounted on it in a series of ‘s’ shapes. The tube should also be black.
Details
The cold water tank can be a plastic beaker with a hole drilled in its side near the base so that a thin rubber tube can be attached. Clamp the tube at the top before starting. Connect the cold reservoir high up so that the water pressure will force water down through the long tube. Turn on the lamp to start heating the metal plate and then release a slow trickle of water. The water at the bottom should be warmer than that at the top.
Tips: Turn the lamp on a little in advance to allow the board to heat up a bit. You can also use ice cold water for the top reservoir; this causes the water to heat up due to the room temperature as it flows down the tube – it is cheating but works well.
Safety: Take care if using mains lamps – keep away from water.

Activities and extensions
Investigating solar panels
The students could investigate the energy output of solar panels. This provides an important opportunity to develop or assess investigative skills. There are two main variants:
• Investigating how the energy output is related to the area of the panel.
• Investigating how the energy output is related to the distance of the light source from the panel. These students can measure the output p.d. from the panel instead of the actual energy output.
Equipment required for each group: solar panel, bright lamp, sensitive ammeter and voltmeter, leads, metre rule or tape measure, black card to cover parts of panel.

AQA GCSE Science: P1a 4.4 Energy and environment (2 lessons if you do properly)
AQA Specification Link
• Using different energy resources has different effects on the environment. These effects include the release of substances into the atmosphere, noise and visual pollution, and the destruction of wildlife habitats.
• The advantages and disadvantages of using fossil fuels, nuclear fuels and renewable energy sources to generate electricity. These include the cost of building power stations, the start-up time of power stations, the reliability of the energy source, the relative cost of energy generated and the location in which the energy is needed.
Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different energy sources to generate electricity.
Learning Objectives
Students should learn: • About how burning fossil fuels affects the environment.
• That there are severe potential hazards associated with the use of nuclear power and disposal of nuclear waste.

most
To be part of a debate to discuss the issues behind fossil fuels and nuclear fuels

How Science Works: develop an argument and draw conclusions consider how and why decisions about science and technology are made

Teaching / Learning activities (including How Science Works)

Lesson structure
Starter
Run through the spread on page 272/3 quickly discussing main points with the class

Main
Found on site www.upd8.org.uk etc
Nuclear power: the great debate
If done properly this works really well, it involves all members of the class, needs about 30mins for the pupils to get ready for their talk and 40 mins to do the enquiry

Learning objectives
Students will:
Analyse, evaluate and develop arguments about the nuclear energy debate
Present their arguments in a planning enquiry role play

Running the activity
Display page 1. Briefly, get students to speculate what the government’s decisive action might be. Display page 2 – a speech by a new Prime Minister promoting nuclear power. Then display page 3, which presents some of the arguments against nuclear power as slogans on placards at a demonstration. Then divide the class into 7 groups. Each group will represent one role at the Planning Enquiry, except for group 7 which organises and chairs the Enquiry.

Display page 4, which sets the task. Give groups 1-6 cards made from one of pages 5, 6, 7, 8, 9, 10 and a copy of the Argument Grid (page 13). Give group 7 a copy of page 11.
It is very important you choose a sensibly but confident group 7 as they run the enquiry!

Groups 1-6 then do the first task on page 4 – using the argument grid to sort their cards into cards that state the problem and arguments in each of these categories: social, scientific, economic, ethical, environmental and emotional. The categories are not clear-cut – some could fit into more than one category. Foundation students might find it helpful to know that the cards are colour-coded: social = red; scientific = blue; economic = green; ethical = yellow; environmental = orange; and emotional = purple. Cards that state the problem are pink. Meanwhile, group 7 gets on with their first task.

Groups 1-6 then plan their contributions to the Planning Enquiry, using the guidance on page 4. Emphasise that they should use just the most relevant arguments. You might like to limit them to a 90-second presentation or to making 3 main points. They could use PowerPoint or acetates to illustrate their talks. Meanwhile, give group 7 a copy of cards made from page 5 and page 13 and ask them to classify the arguments.

Give each individual or group a copy of page 12. Then get group 7 to use the instructions on page 11 to run the Planning Enquiry role play for the rest of the class. During or just after each talk, get individuals or groups to complete page 12 – this summarises the main arguments of each group and forces them to listen!

Finally, group 7 will lead students in voting for or against the power station.

In order to fully meet the curriculum requirements of HSW 3c and 4b, it is vital to get students to engage in reflection and discussion about how the decision was reached – it is about much more than considering only scientific evidence. You might like to do this after students have de-roled at the end of the debate, perhaps by getting students to consider which argument categories were most persuasive in their decision making. Alternatively – or as well – set the following as homework:
Worries about global warming and fossil fuel shortages are prompting the government to consider building new nuclear power stations. List the main benefits and drawbacks of nuclear energy. On balance, should more nuclear power be used? Explain how you reached your decision.

Plenaries
The final vote for nuclear power and discussion/reflect on the issues

Teaching suggestions
• Learning styles
Kinaesthetic: Researching into decommissioning costs.
Visual: Presenting research data. Auditory: Listening to news reports of disasters.
Interpersonal: Debating the impact of nuclear disasters on the environment.
• Homework. Ask the students to work out how much money they could save each year if they replaced all of the light bulbs in their house with energy saving ones. They need to find the power rating of the bulbs to do this.
• ICT link-up. The students may like to research the details of the Chernobyl disaster. A lot of material is available on the Internet from a simple search, but they will have to be careful to find information at the correct level for them to understand. A PhotoPLUS, P1a 4.4 ‘Chernobyl’, is available on the GCSE Science CD.

• Teaching assistant. The teaching assistant can support some of the debates and provide ideas to students.

Learning Outcomes
Most students should be able to:
• Describe how burning fossil fuels affects the environment.
• Describe the ways in which using renewable energy resources affect the environment.

Some students should also be able to:
• Explain and debate the issues relating to nuclear energy and fossil fuels to generate electricity.

How Science Works: develop an argument and draw conclusions consider how and why decisions about science and technology are made

Activities and extensions
Copies of sheets
8x sheets 1 to 3
20x sheet 4
6x sheets 5 to 11
4x sheet 12
6x sheet 13

AQA GCSE Science: P1a 4.5 Big energy issues Optional lesson could be given for H/W
AQA Specification Link
Students should learn: Students should use their skills, knowledge and understanding of ‘How Science Works’:
• to compare and contrast the particular advantages and disadvantages of using different energy sources to generate electricity.
Teaching suggestions
Activities
The big energy debate – The UK has signed up to a treaty to reduce carbon dioxide output; how can this best be done? Assign students (or small groups) a resource to research and present information about. After the presentations, the students vote on which resource should be used. A project like this will probably last at least a couple of hours, and it is best not to show all of the presentations; just choose the best one for each resource. As a slight alternative, the students could be provided with the information and take part in a debate with roles assigned to them by you. You could film this if resources are available, or if a media studies group want some practice.
Summing it all up – The students could draw a mind map linking all of the ideas from this chapter. This should be a big colourful poster-sized piece of work if possible. You can show or give them a template to start them off. The idea behind a mind map is that it should be drawn several times to set the ideas in the mind. The students should redraw their maps during the examination revision process.
Extension or homework
Nuclear waste storage – For homework, the students could find out about how and where nuclear waste is stored. What are the plans for dealing with it in the future? How is it transported from place to place?
Teaching assistant
The teaching assistant should join one of the groups with least confidence to help present their side of any debate.
ICT link-up/activity
Clearly this chapter lends itself to a research project in which the students find out about the costs and benefits of various resources. The students could be given a set of scenarios and produce a presentation showing possible solutions to the energy needs. For example, the needs of a large industrial city might best be met by a gas-fuelled power station, while an island community may opt for a tidal barrage or even wave power.
Learning styles
Kinaesthetic: Researching about nuclear waste.
Visual: Drawing a mind map.
Auditory: Discussing environmental problems.
Interpersonal: Debating issues.
Intrapersonal: Evaluating solutions to energy demand.
Gifted and talented
How close are we to getting nuclear fusion to work? Students could find out more detail about the progress that has been made and some of the problems that have been discovered:
• Nuclear fusion is a technology that may meet all of our energy needs one day, but even though the science is well understood it has proven very difficult to design and build a working reactor. How far off is one?
• Nuclear fusion is also not entirely clean. The reactor components may become radioactive after use, although not as dangerous as fission reactors. How does this happen?