Rocket Science for Kids: Stomp & Water Rockets

The Physics Behind Every Rocket

All rockets demonstrate Newton's Third Law: for every action, there is an equal and opposite reaction. Gas or water shoots out the bottom (action), rocket flies up (reaction). The more mass you expel and the faster you expel it, the higher the rocket goes.

5 Rocket Projects

1. Stomp Rocket (Ages 4+)

Materials: PVC pipe (2ft), empty 2L bottle, foam, cardstock, tape
Build: Connect PVC pipe to bottle opening. Create paper rockets with nose cones and fins that slide over the pipe. Stomp on the bottle — air pressure launches the rocket 50+ feet!
Physics: Air pressure, force = mass × acceleration.

2. Water Rocket (Ages 8+)

Materials: 2L bottle, bicycle pump with needle adapter, cork, cardboard fins
Build: Add fins and nose cone to bottle. Fill 1/3 with water. Insert pump-connected cork. Pump to 50-60 PSI. Release — rocket flies 100+ feet!
Physics: Water is heavier than air, creating more thrust. Demonstrates conservation of momentum.

3. Film Canister Rocket (Ages 6+)

Materials: Film canister (or plastic pill container), Alka-Seltzer, water
Build: Add 1/3 water and half an Alka-Seltzer tablet. Snap lid. Place upside down. Wait 5-10 seconds — POP! Rocket launches 10-20 feet.
Physics: Chemical reaction produces CO2 gas, building pressure until the lid releases.

Launch Data Collection

Turn launches into science experiments:

• Measure flight time with a stopwatch
• Estimate height using a reference object
• Change one variable at a time (water amount, fin size, nose cone shape)
• Record data in a table and graph results