[Edit: The feet were upside down in my first attempt, as you'll notice in the pictures. I wasn't paying attention. I fixed it in the new version.]
This jumping jack was made using athey's skeleton as inspiration. I've reworked it a bit to make the joints work with paper clasps instead of rings, for sturdier movement and easier assembly by children. I know Halloween is a long way off, but we're teaching kids how the skeleton works for a few weeks this summer, and I wanted to have something they could make and bring home with them.