Just start! My 13 year old grandson started when he was 6 and now runs my mid-arm like a pro, better than I. He has entered a qult only once but got a first place and Best First quilter.
My 8 year old granddaughter entered 2 quilts in the columbia county Fair last month and got a Best of Show.
When they WANT to learn they will with a little guidance. Have FUN.