SDI has Future Buddies. They can dive with an instructor in confined water not deeper than 6 meters. My daughter did it, and I have trained quite a few in it. It all depends on the kid.
And then at 10, junior Open Water cert- 12 meter limit until 12yrs old and madatory dive with parent.
And then at 10, junior Open Water cert- 12 meter limit until 12yrs old and madatory dive with parent.