Between a semi-auto .22LR rifle and a bolt .223, which would be better to train a kid on once they've gotten some time behind a BB gun? My father's got both and several hundred rounds of cheap .223, and given how hard it is to get .22LR right now...
I would recommend the bolt-action .223. Mostly because the bolt action will encourage a bit more deliberate aiming than a semi-auto. Depending on how much he takes to shooting, he can use that .223 later in life for longer range shooting, hunting, competition, etc.
Nice gun for sure, but I'd need to get the 5", and that little bolted on extension looks a bit silly! (Canada prohibits pistols with barrel length of less than 4.1")
That's too bad, really. I have a P22 and it's a fun little gun. In any case, I believe there are a couple 1911 style pistols in .22LR and I believe S&W makes a .22LR version of their M&P line.
I chose the P22 specifically because it operates nearly identically to my other pistols (with two notable exceptions). When I'm teaching new shooters, they can transition from the P22 to the S&W with just a couple of pointers (and from there to the Glocks with even less work).