Then we together looked at which size jump "fitted", so that the jumps only went round once to create nice neat petals.
Meanwhile, Rose, Marie and Gabrielle volunteered to try a similar thing with Cuisenaire rods. Their line of rods had to be 60 long. Only numbers that "fitted" exactly into sixty could be added.
They did a great job. The line at the top is the twelves, made of ten+two because we don't have any twelve rods. Can you see any other big factors of sixty that are missing?