The problem with watching video (tv, video games, computer, etc. ) constantly as a young child is that the brain is not fully developed. There's a growing body of evidence suggesting that the brain is even being wired differently because of it. What does this mean? I'm not sure, but I would personally say that it accounts for the ever-increasing prevalence of ADHD as children. These children are not able to focus on any stimuli for a length of time as they should. So, how do you teach a child who can't focus for more than two minutes at a time? These children (as often as not) present with lower academic scores and abilities, are impulsive, and make careless mistakes even though they have average IQs.