The first reason pets should not be in classrooms is that they can cause health problems for kids and themselves. One example is during weekends or anytime they're left alone in their cage uncleaned it can develop bacteria and may trigger disease. Another example is the pets can be allergic to the kids and trigger disease like ammonia.
The second reason why pets should not be in the classroom is that they
are usually not treated well. One example is if something happens like a fire and, the kids or teacher is not there than who will get them if something happens. Another example is how much they are fed most of the time if the teacher asks a student to feed the pet they can give it too much or too little or none at all which is bad because they could suffer and, starve over weekends.
So having a pet in classrooms can be beneficial for kids but, not for the pet itself. They often die from health problems or not being treated properly. So we should help these animals by not letting them suffer in are classrooms.