I think that, more than anything, is why most kids only practice one or two days a week. As far as the practices themselves, the biggest rule of thumb that a coach should follow is that he should give his kids homework. He or she should provide the players with a specific activity that he wants them to work on, and tell them exactly how many repetitions he wants them to do. For instance, if he wants them to practice their dribbling, tell the players to dribble the ball 50 yards, and do that 15 times. This way a player can understand exactly what the coach expects of him.
Shoes are really the only equipment one needs to play.
I used to work at a soccer store. But many parents, when they purchase shoes for their very young children, attempt to buy shoes that the children can get several seasons' use out of. So, essentially, they're buying shoes that are two or three sizes too big. This makes it very difficult for the children to play the sport, because a lot of them will end up tripping over their own feet, and it makes the children very frustrated. This will just ensure that the child is given the opportunity to perform a sport without getting frustrated.