Hey ChrisT,
When I was 14/15, I was burning up cars of people that went parking in the woods, throwing propane cylinders into trash fires and shit like that, stealing bikes and sailboats for joyrides, and generally harming little defenseless animals (I'll stop right here and leave out the rest...).
At 15, I got a job as kitchen help for some meager pay and free room and board at a rich kid's summer camp in the mtns. Learned all about pot, girls, and other stuff, but being away from the folks for 3 months straight caused me to learn to do most shit for myself and to stay out of trouble.
Maybe something like that, where he's away from you guys, earning his own money with no place to spend it (mostly), responsible for his own actions and getting his own ass out of the sling when he gets in one, but not being forced to do shit like kiddie boot camps make you. Changed my life. YMMV