My daughter is 5" 100 lbs. she shoots the edge with 30-40 # limbs. Take him to a shop and have him draw both weights, if he can draw the 30-40 fine, if he can't go with the 29. the draw length adjustment built into the cams will allow him to grow with the bow and if he continues to shoot the edge you can purchase 30 -40 # limbs for it, (even 40-50's if you keep it long enough).It is a great bow for youth and small shooters.