The gymnast you have created converts linear motion (in a straight line) to rotational motion (in a circle). When you pull the skewers apart the string tightens, making the gymnast turn upside-down. When you push the string together the gymnast wants to fall. If you time it right, the gymnast completes the flip.
Once the gymnast starts spinning, its angular momentum will keep it spinning until the twist in the string makes it stop and start spinning the other way. By timing the pull and push on the strings, you can get the gymnast to do multiple flips in a row.
Mess Kits are single-serving experiments that allow kids to explore scientific concepts at their own pace. Visitors are encouraged to complete as many as they want! See all Mess Kits.