This is the age that some boys will hit puberty separate from the later bloomers. My kid is on age 2023 (Turns 14 this December) and he's 5'11" 145lbs and had to start shaving last year. I'm sure most who see him on the field think he is a "holdback" or "pre-first" and neither are the case. Looks can be deceiving so stop judging and look for the best experience for your son. The "best" team is where a player enjoys playing and is driven to improve, not necessarily the one with the best record.