Lesson - Milk Carton Water Wheel

milk carton water wheel


Title: Milk Carton Water Wheel
Grade: 4th Grade
Duration: Two – 45 Minute Lessons



Will the water placed into the milk carton come out evenly? And, will it create an equal reaction from all sides?


This experiment is an investigation using Sir Isaac Newton’s Third Law of Motion – which states that every action has an equal and opposite reaction; as water shoots out the holes, and pushes back on the carton with equal force. A turbine is formed as the energy of the moving liquid is converted into rotational energy.


  • 12 inches of String
  • Disposable aluminum tray 9×13 or larger
  • 4 empty and cleaned out 32 oz Milk Cartons
  • Pencil
  • Ruler
  • Scissors
  • Water
  • Paper


Individual Experiment

If you are going to have all students do it there is a little prep time for this activity. But it can easily be done as kids finish other assignments. Have students save 16oz milk cartons from their school lunch and rinse them out in class beforehand.Let them dry thoroughly or you’ll have a very stinky room!

Group Experiment

On the day of the experiment, divide kids into groups. Each group should be given a tray. Have students measure out 12 inches of string for the 32oz milk carton (if you have an 18oz milk carton use 6 inches).

  1. Poke a hole in the bottom left hand corner of each of the four faces of a half-gallon, paper milk carton.
  2. Now poke a hole in the top flap of the milk carton. Tie a string through this hole.
  3. While covering the holes in the milk carton, pour water into the carton.
  4. Suspend the carton in the air by holding onto the string only.
  5. Now take your fingers off of the holes.
  6. What is your observation?Was you hypothesis correct?


  • What is energy?
  • What are the different forms of motion?
  • How can moving water create energy?
  • What are the types of energy that can create force?
  • How can we use the energy of motion?

What’s Happening?

Have you ever held a toy under your running bath water? Did it spin or twist away from you? This is explained by Sir Isaac Newton’s Third Law. Specifically, the law states that ‘for every action there is an equal and opposite reaction’. 

Activity and part of the sequence were adapted from: Reeko Science


Hydropower 1

Hydropower 2