Many researchers have found that there is a strong link between viewing television habits and children performance in school. Most researchers found that children who spent most of their time watching television get a lower grade in school than their friend who watching television fewer.
This activity also affected to their ability to communicate with other people, they spent to much time to sit and follow the story in the glass screen, that make them don't have a time to learn a physical activity which stimulate more nerve and logic. television then led children to be more passive than active.
They also believe that television doesn't have so much program which have an education value, a program like cartoon movie, are only have a little education value.
Actually i do agree with their conclusion, but i'll tell you a story about my friend who spent his childhood in United States. When he is at 3, he spent so much time watching television which show a reading and writing teaching program, his nanny give him a paper and pencil to write. he did it almost everyday, after about a month he already able to write and read without anyone at home teach him directly.
Well so then i think it's not about watching television or what, it's about the program they watch, and the time management also i think. A smart parents have to know which program are good for their children, and which program are not, and they also have to manage how much time that their children have to spent in front of the television and how much time they have to spent to play any physical activity.