That photo is PRICELESS! I hope you keep their first efforts to show them in a few years. I was about that age when I learned (left-handed from a right-handed mother -- LOL!)
Its also called spool knitting or corking. You end up with an I-cord, which isn't all that useful, but the kids get a long 'sausage' or 'snake' pretty quick, which they love.
I loved doing that as a child. My Mum saved me her big empty thread spools and my brother would pound 4 nails into the top and I was off. Don't remember doing anything useful with the I cord but it was fun. The picture of your children is a keeper. So cute.
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If I'm sitting I'm knitting!
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