“2-liter soda bottles turned water rockets are as shrieking good a time as a water park and a lot easier to build! They streak into the air faster than the eye can track while dousing everyone in the launch area with water. Occasionally, my middle school students host and teach classes of elementary school kids from across the street to make a take-home science project, and we always finish off with a couple of launches. Years later, when I teach those now-middle school kids, they never remember me, but invariably remember the water rockets!”
This looks like tons of fun!