We have a moderately strict rule about electronics time at the house -- as long as their homework, chores, or other responsibilities are finished, each kid gets to play a computer or video game for an hour plus watch TV/movies for an hour. We also have an "electronic-free" day every week, where nobody (not even parents) uses the TV or computer. This has so far worked quite well for the nine-year-old. However, we're running into trouble with the five-year-old.
When he's told his time is up and the game needs to turn off, or the TV show is over and it's time to do something else, he gets angry and throws a tantrum. Generally this includes denying that the right amount of time has passed (even though we use a timer), claiming that he wasn't paying attention, insisting that he didn't have a good time and so he should get to start over -- the excuses are often fairly creative, come to think of it. He's not picky about games -- whether it's the computer, my phone, even a random stranger's iPad, he will ask to play with it and get angry if he can't.
He can play happily with blocks, cars, legos, dirt and sticks, and other things, but when he's focused on getting back to a computer game, he insists there's nothing enjoyable besides the computer game. He doesn't perceive it as fun unless there's a battery or power cord. Should I worry about this, and/or try to channel his enthusiasm in a different direction?