Propellers and Pinwheels

Build and test a mini wind turbine, pinwheel, or decorative wind spinner. On a plane, a motor-powered propeller spins to push air. On a wind turbine, a rotor spins when pushed by air. How do the number, shape, and position of the propeller or rotor blades affect the rate of spinning? Experiment and find out! 

Materials: 

  • Electric fan (or a breezy day outdoors) 
  • Cardboard 
  • Boxboard (thin cardboard)  
  • Scissors 
  • Tape 
  • Brads (a.k.a. brass fasteners; if not available, can substitute pencil, straw, or toothpick) 
  • Toothpicks or wooden barbecue skewers (optional) 
  • Markers or colored pencils (optional) 
  • Scraps of fabric, trash bags, or other flexible materials (optional) 
  • Bendable wire or pipe cleaners (optional) 
  • Hot glue (optional; adult supervision recommended)