Well the u14 boys are getting to that age where they are trying to figure out where they belong from a status standpoint. Attitudes start to form, but this is the critical age when they either still love the game or not. Keep the game fun for them and make sure that they don't see it as a waste of time. If you can do that, the boys will stay and respect you. If the practices are boring or they think they can be doing something else, you will lose them. BUT.....don't put up with any crap from the 1 or 2 kids who are trying to be the "cool guy". Set the standard early.
I can't really help with the u15 girls because I never coached that age, but from a year younger, they will act more like a team. Get them bonded early so you can have all of them working for a common cause. Very brittle at that age.
