This from an article in the New York Times on the use of video games as a pedagogical device:
"Neuroscientists have connected game play to the production of dopamine, a powerful neuro*transmitter central to the brainís reward-seeking system and thought to drive motivation and memory processing (and more negatively, addictive behaviors) ó all of which could have implications for how, when and what type of games should be used to advance childrenís learning. But as it is with just about everything involving teaching and learning, there are no simple answers. Games, for example, appear to trigger greater dopamine releases in men than women, which could mean that game-based learning is more effective with boys than girls. Or, says Plass, it could be a matter of design: ideally, games can be built in such a way that they adapt to the individual learning styles of their players."
For the most part, television was a massive failure as a educational tool, laptops are mostly a distraction, most of those "Baby Einstein" type of educational video toys for infants actually degrade development.

Mostly infants, children, and teenagers need more adult time, attention, and conversation, and technology just gets in the way (while eroding a school's budget).