My son (13 yr old) started playing with me this year. I've been playing since 1992. His excitement to go play with Dad hasn't met up to his experience on the field yet. We've played a few walk-ons an there have been way too many people on the field each time we've gone. It's turned into massive amounts of paint right from the whistle and he hasn't lasted much past a few minutes. He is playing very aggressively, which is why he's getting out. We've got a private game coming up soon which may help him enjoy himself a bit more.
It's fun playing with your kids!