I had my own old hand crank sewing machine when I was 5. Ran a needle through my finger. After that mom let me piece old rags together on her FW to make rag rugs for my Great Aunt Goldie to weave. The Lady's Aid made quilts and I hung out with them. By the time I was six I helped make the dress I wore to school the first day of first grade. That was before I learned to write my own name. I would start with hand sewing a piece of plastic mesh and a pipe cleaner or take greeting cards and punch holes and sew them together with a big blunt needle. If they can write their name and do mazes with a pencil and do dot to dot accurately, then I would let them practice sewing on paper with no thread. 4H had the right idea of giving them an operator's license - had to follow the lines on paper, know all the machine parts, etc. I think learning to sew at a young age is great but not too young. Developmental people say they need to learn to use their large muscles first, then the fine skills will follow. Some recommend teaching a kid to use large muscles for the left arm and fine for the right if they are right handed - reverse it for lefties. I'd say maybe 7 is a good age to use a sewing machine for girls - older for boys. Let them be kids a while - on the other hand they do need to learn some time or it will all be forgotten.