We in Canada have a Cadet Corps (Army, Navy, Air Force). They are teenagers who are involved in militaristic/fitness training. As far as I know they get to fire .22 rifles and I have never herd of a rifle jumping in their hands and killing anyone. It must be a special Canadian air.
I'm assuming you realise the difference between a 9yr old with an Uzi and a teenager with (probably) the lowest powered semi-auto/bolt action rifle money can buy.