Make 582
OK, I’m posting this again because we have a cool new logo – The King of Fling contest at Maker Faire, organized by Bill Gurstelle, author of Backyard Ballistics – There are two different classes in the contest, both involving water balloons. One is a target shoot and the other is a face-off against each other. Bill has provided instructions on how to build a small catapult. So, download the King of Fling manual, build a catapult and register for the contest.

The King of Fling contest – Link.