but you want the kids to learn to actually play the game, and play it the correct way so that when the other teams get bigger and more athletic, or get proper coaching, they aren't left behind with their bad habits. just getting real, proper blocking down takes years for kids to learn.
it's like in basketball. those athletic teams whoop up on you when you're a kid, but if you get brilliant on the basics, you'll see those white teams that rain threes all day long, work over the more athletic teams.