I bought my son a Browning Micro-eclipse when he was about 12, and he used it to hunt with until he was 16.

Draw weight was adjustable from 25-45# (although it actually went higher - 52#) and draw length is adjustable to 26". It was perfect - as he grew and got stronger, we could keep adjusting both length and weight, and it is a true quality bow. I highly recommend it.

Remember, though their are legal (and ethical) limits to how low the draw weight should be to hunt. NY state is 35#, but Mike didn't hunt deer with it until he could draw 45#.