If your son turned fourteen on or after May 1st he's eligible for 14u next summer. But given he will be a freshman in high school it's highly advisable he starts playing with his grade rather than his age. He should play 15u. He's actually at the point where he should be playing up as far as his talent will allow. But 13u to 15u is enough of a jump. 13u is somewhat slow motion baseball as kids get accustomed to the 60/90 field. The game starts to speed up after 13u.