A couple of years ago, I started shooting clays and PSG using my late father's pump-action shotguns. While you may not hit as many clays as with a boring over-and-under, they are *much* more fun.
Also, if'n they start using pumps, they should have no trouble using anything else. (When they learn to drive, if they learn in a manual car, they'll have no trouble driving an auto, either.)
Regards,
Mark.