From my point of view, movies and television have more negative effects than positive effects on the way young people behave.
First, movies have negtive effects on young people. There are many movies containing some violent and bloody scenes advocating the so-called brotherhood,which is indeed a presentation of the will to maintain interest and power for which the gangsters groups fight through violent conflicts.Take the famous American film "Once upon a time in America" for an example: youngsters especially boys were influented by the film and became inclined to imitate the roles in the movie,beating their classmates and talking dirty.
Another bad situation lies in Japanese anime presented in films and broadcasted on TV which can block more active, direct involvement in real life. Due to the negtive effects of these animations, young people can gradually form an unsocial personality. For instance , several classmates of mine are crazy about watching Japanese absurd anime specially that of sadness and eschatology. And they barely go to class and even do not attend group activities, eventually become lonely and incommunicative.
Admittedly, movies and televisions ,to some extent, have some positive effect on the way young people behave. For example , young people could have access to fress news about what is happening across the world and latest criticisms and comments on international events. Meanwhile, younsters can also watch some talk shows talking jokes and funny stories which make people relaxed.However, these substantial infomation innundating have an obvious flaw. That is the way TV operates is unilateral. People tend to regard what they have received from TV is always true. But,the fact is , lots of TV shows create controversial topics of discussion just to attempt to win audience ratings, thus, the aggressive comments in these shows are probably misleading young people.\
From what has been discussed above, there might be one or two positive effects of movies and televisions on young people's behavior, however,I believe that there far more negtive effects.