BrackaFish
Contributor
SSI has a Scuba Ranger program that is limited to pool and depending on the instructors can be a lot of fun. My oldest boy did that and enjoyed it tremendously. With my youngest, we waited until he was almost 12. As @caydiver, @tursiops and others have pointed out there is not a great deal of information about the effects of increased pressure on tissue, growth plates etc on young kids. Mental maturity is also a big factor as I have dove with some fifty year olds that I questioned were old enough to dive. Good luck.