This has been a good thread for me to read, as I have a curious and active five-year old. He's not ready for the range yet, and my guns stay locked in a safe. I picked up some excellent information on how to work with him as he grows up.
Just a side note--toward the beginning of the thread I followed the link to "Cornered Kitty" and found the 1932 photo of the 6-year old with his .22 and a brace of jackrabbits. Someplace I have a similar one of myself as a kid in the sixties with a pheasant and my 20-ga bolt action Marlin shotgun.
I lived in a rural area, and everyone I knew had guns in the house, usually shotguns or rifles of various description, hanging over the the fireplace or leaning behind the front door or in a corner by the nightstand. If they weren't loaded, the ammo was right nearby. Most of my male classmates from about sixth-grade on were gun owners. the thing is, I can't remember anyone who would even have thought of messing around with one of his Dad's guns when no one was around, and my friends and I spent long hours hunting and there was absolutely no screwing around with firearms. Times have sure changed, and not for the better as far as guns are concerned--on several levels, eh?
Nonetheless, this is, again, a very important thread. Maybe it'll save a life or two.