DD started "whittling" when she was 8. She owns her own pocket knives. Her and dad often do a bit of carving on camping trips. At first, all they did was make kindling for the campfire but she is getting better.
I think DD is ready but if I let her do it, than DS will want to as well. He will be five this summer. But, his hand - eye coordination is much more advanced than DD was at his age. And he loves knives. God help me with this one. Lol.
If he loves knives, at least teach him knife safety. DD could use our knives before she owned her own but she had to ask permission to access them and give them back to us as soon as she was done. I just wish they'd make carving gloves in children's sizes.
My DS learned knife safety and usage through boy scouts. They had to go through a process and demonstrate a bunch of stuff (I don't know the details) before they're allowed to carry a knife. (It's called their totin' chip meaning they can tote a knife). My DH said that was when they entered boy scouts which starts 5th grade here. They can have their totin' chip taken away if someone sees them handling a knife incorrectly or dangerously. Cub scouts who are younger are NOT allowed to carry them. DH said they didn't even really work with knives much during cub scouts which is under 5th grade. Five personally seems really young to me, but my DS had poor small motor skills.
Not yet though my oldest just turned 6. I am trying to get her into knitting. She has a loom project. I think we will bring that camping with us. Its a cool idea with slightly older kids. I know DD will start a small amount of knife safety this year at GS Summer camp