In our AYSO league there is no ref for the first few years - the coaches just call the game. If your league has refs, then this isn't applicable.

There was a big difference between how some coaches wanted to run things (ball is out once it goes over the line, etc.) and how others thought it should be run (kids could dribble 20 yards out of bounds and then back in and play just continues).

The thing that was hard for our kids was that they had leaned to stop when the ball went out of bounds and to restart the game with a throw in - but some other coaches would just let play continue and our kids would stop and watch while the other team kept playing and took the ball down the field. We tried to tell them to play until they heard a whistle but once they know a rule they can't understand why someone else should be allowed to break it.

I don't have a major problem with either approach as long as its agreed to by both teams.