Boing

The grand-kids didn't know how to play boing.  A three person game played on the tramp where you take turns jumping across the length of the tramp landing on your bum, where the person standing parallel to your landing position steals your bounce to bounce across the tramp and land on their bum on the other side.  After you have jumped and landed on your bum and your bounce has been stolen, you stand up and take the place of the person who just stole your bounce to repeat the cycle.