Ideally, none. I don't have kids, but I've seen some really negative impacts of TV on little kids in my acquaintance. As a kid I was allowed 2 hours a day, but that was only in summer when there was "nothing else to do." During the school year there was hardly time for TV--maybe an hour of cartoons in the evening, if that. From what I've seen, TV is a passive activity for kids that doesn't require them to learn to focus on anything--because they don't have to interact with it. In addition, kids whose TV-watching choices aren't well monitored can learn obscene language, be exposed to unnecessary violence, and "adult" themes that they have no need for. Forgive me for my soapbox; but in my opinion, it's much better to get kids reading or doing something creative (Play-Doh, coloring, finger paints, helping make cookies) than to plop them in front of the TV and let it do the babysitting.