Agree with the notions above about fit, low-recoil, practice, even maybe coaching.
Now it wasn't said what was to be shot/hunted. But, as to the OP's question would say "either" if it's sporting games like skeet, but pump if it's any hunting. We're talking 10yo boy, just starting out, remember that time? He has enough on his mind between safe firearm handling, basics of shooting, the excitement of seeing game and being "out there", and guidance from dad in the other ear. Not to mention Susie that sits across from him in reading class. It's a lot at that age, or any age. I think there's a lot positive to be said for a bit of manual mechanical simplicity and having immediate control of when the gun is chambered or not, in the field particularly.
And I like a semi-auto, too, but while can see some possible liability, I don't see at all the auto's (small) upside ever being a real positive in this circumstance.
Anyway, it's a cool, foggy late-fall morning, sun peaking through, the steam rising from the creak below. Just took the dogs through there. Shortly will head up to the range to exercise a 1927 M12 and a 1956 A5 light. Both 16ga. Good times.
