cool. remember "perfect practice makes perfect". start him shooting with proper form and technique, don't let him develop bad habits.
most states have a minimum of 40 lb draw to be legal to hunt with. 40 doesn't sound like much but until he gets his muscles trained, it is. be sure to have him not push the weight to fast cause he can hurt himself. oh very important, never ever dry fire a bow. never shoot it without an arrow in it.