In this tutorial, we learn how to make a fast and easy tennis ball trebuchet. This tool will throw tennis balls easily so you can hit them without having a partner around. This only needs a few pieces of wood and 2x4's along with dumbbells. There isn't a whole lot to this, it's very simple to build. Use two 10 lb dumbbells clamped with a hose clamp onto the top of a 2x4. Use a dowel to go through this, so it will help it rotate. Down at the bottom is the release mechanism and on the sides will be pieces of wood to hold it all in place. Place a counterweight at the very bottom and then when you're finished you can use this to throw tennis balls!