Make Your Own Windmill
Take a load off! Learn how to use the power of wind to lift an object.
About the Activity
Wind is a powerful force of nature. And you can make it work for you! This 4‑H STEM Lab experiment introduces kids to mechanical engineering and wind power by showing them how wind can be converted into energy. In this activity, kids will build a simple windmill and use it to power a pulley system to lift a bucket.
Grades: Pre-K – 2
Topic: Mechanical Engineering
Time: 30 minutes
These simple materials will get you started.
- Cardstock or construction paper (thicker is better)
- String (cotton or twine is best)
- Paper clips
- Rubber bands
- Large disposable cups (rec 16oz) or round oatmeal container
- Small disposable cups (rec 6oz)
- Large straws
- Small straws (not bendable preferred, wood skewer or a pencil can also be used)
- Hole punch
- A box fan or blow dryer
- Crayons, markers or other materials to decorate their windmill
- Stopwatch or timing device
Before beginning this activity, think about this: Wind is moving air caused by differences in pressures in our atmosphere. And harnessing wind power isn’t new, either – wind has been used as an energy source since at least 3,000 years ago in Persia (modern day Iran) in the form of windmills.
- Use the attached windmill pattern or cut out a 6.5” by 6.5” square.Did You Know? You are building a simple machine. Simple machines are things like an incline, lever, pulley, wedge, and wheel and axle. They can change the direction or power of a force.
- Mark the center of your square and cut from the corners diagonally towards the center of the square, stopping about 1.5” from the center point.
- Use scissors or a holepunch to make a hole in the center and at the end of every other one of your 8 corners. The hole should be large enough for the small straw to fit into.Fun Fact: Complex machines are any combination of simple machines, like a bicycle or a wheel barrow.
- Push the small straw through the center of your square and then bend (don’t fold) each of the corners onto the straw.
- Secure the front and back of the pinwheel with tape, a paper clip or rubber bands to keep the pinwheel together. There should be about an inch of space between the front and back of the pinwheel.
- Cut the large straw so that it is equal in length to the bottom of your large cup and secure it there using tape.
- Slide the end of your small straw through the large straw on your base. There should be about 1.5 inches of the small straw that extends past the base. You can trim the small straw if needed.
- Take your small cup and cut two holes in opposite sides and tie a small piece of string between the two holes, creating a sort of bucket handle.
- Secure one end of your string to the end of the small straw and tie the other end to the small cup handle.
- Place tape or a binder clip on the end of the small straw to keep the pieces together.
- Now blow on your pinwheel and watch it lift the small cup!Did You Know? A windmill is a simple machine called a wheel-and-axle machine. What does that mean? It's a wheel attached to a rod or spindle that helps transfer forces. Both the millstones and wind turbines are examples of simple, wheel and axle machines just like the machine you built! Wheel and axle machines are the foundation of many other mechanical inventions, like the bicycle.
Add one penny at a time to see how much your windmill can lift.
Questions for your kids and teens.
- What improvements or adjustments might make your design work faster or make it stronger?
- What is the maximum number of pennies your machine is able to lift?
- How long does it take your machine to lift the cup? What about with four pennies or eight?
Investigate and Explore
Take what you've learned to the next level.
The next time you see a windmill along the highway, consider this: There are many modern designs of windmills, but the underlying design principles haven’t changed in 3,000 years: The wind pushes against the blades and turns a center shaft. In the past, the shaft was connected to a pump or to a millstone used to grind grain.
But as we look to the future, wind is likely to make up a greater percentage of our power production because it is considered a renewable energy source, unlike fossil fuels like coal.
Rural STEM Careers
Wind power is an industry that is growing across the country. Did you know that rural areas are experiencing shortages of qualified STEM workers who can provide vital services to often under-resourced areas?
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