It greatly depends on the maturity of the child.
I tried unsuccessfully with my youngest when he was 10. I got quite a few gray hairs in the process. No matter how patient I was or how careful, he still wanted to go at warp speed! Which is not a good thing with sharp objects. I finally told him that I would do all the cutting and he could do the sewing. That was scary enough.
He made a couple of things then lost interest. Doctor said he was border line ADHD. When he became a teenager, he did a complete 180. Sometimes so slow a turtle could pass him!
Oh well, each child is different.