Water rockets are really cool! We made our own water rocket using recycled materials that you can find around your house and then launched them in a nearby park. We had a lot of fun running around trying to catch them as they fell down from the sky.
Some things we observed:
1. You can launch your water rocket about 4 times before the fins start coming off.
2. The less water you put in your rocket, the higher it will go.
3. The more air you pump into the rocket, the higher it will go (but this also makes it a bit more dangerous when launching, so be careful)!
If you would like to make a water rocket, here's a list of supplies you'll need:
16 oz water bottle
cardstock & cardboard
paper towel tube
fabric scraps or construction paper
ruler & marker
ping pong ball
There is a special launcher we use, manufactured by Pitsco. However, you could craft one yourself using some PVC piping, rubber tubing, and bicycle pump.