Studies from the American Academy of Child & Adolescent Psychiatry estimate that the average child spends three to four hours a day in front of the television set. A 2001 study done by the group found that children who watch an excessive amount of TV are more likely to be overweight, read fewer books and do poorly in school.
As stated by The Museum of Broadcast Communications, the catharsis theory believes that television serves as an outlet for purging aggressive actions and that children who watch it are less violent than others.
On the flip side, The Museum of Broadcast Communications states that the stimulation theory holds that violence on television is apt to make children more aggressive. A series of studies investigating both stimulation theory and catharsis theory found the former to be much more likely.
Studies cited by the Museum of Broadcast Communications show that children are more likely to be aggressive after viewing violent material on television, but that the effects are not strong enough to counteract parental influence and other behavioral factors.
Shows like "Sesame Street" and "Mr. Rogers' Neighborhood" have shown the positive influence of television on children, encouraging them to learn through catchy jingles and colorful characters.