I was allowed to carry a pocket knife if I was with my dad when I was 7 and full time when I was 8.

I made a very nice little fixed blade for my nephew when he turned 8 (with my sisters o.k.). Sized for smaller hands, black linen micarta with some nonslip checkering cut in it, ATS-34 steel, and a hand stiched leather sheath with the belt loop on a swivel ring. He got the whole being responsible speech and how I would take it away if he did anything irresponsible with it. He was very good with it. Had a hiding place where he kept it. I also explained to him how a dull knife could be more dangerous than a sharp knife because it takes more effort to cut something. "So bring it back to me and I'll keep it sharp." He would bring it to me and it would look like he was trying to cut rocks with it! I did keep it sharp for him. He spent a year deployed in Iraq and he had it with him.

I've got a little boy that will be 5 this summer. I'm already planning on the knife I will make him. I've got some hunter orange G10 I think I'll use for the handle. Kinda thinking on making the sheath with a built in LED light and a small firesteel in the handle. Maybe the other way around. However I do it, it will be cool. The kind of thing that stimulates the imagination for adventure.

For a folder, Victornox makes a pretty good first knife for kids. Has a rounded point. Think it's called "my first knife".