Wind Power Experiment: Build a Paper Wind Machine That Lifts a Load

Wind turbines look simple: blades turn, electricity comes out. But which blade shape works best? That’s an engineering question students can test with paper, a straw and a fan.

What you need

A paper or plastic cup (about 350 mL)
A plastic drinking straw
A wooden skewer with the sharp point snipped off (an adult does this), thinner than the straw
Cardstock or file folders for blades
Modelling clay or a cork for the hub
Thread or string, paper clips, tape and scissors
A fan on low or a steady helper blowing through a tube

Build the wind machine

Push the straw through two holes in the cup’s sides so it works as a bearing.
Slide the skewer through the straw. Attach the clay hub to one end and four paper blades to the hub.
Tape a length of thread to the other end of the skewer, with a paper clip tied on the far end.
Place the machine in front of the fan. As the blades turn, the thread winds around the skewer and lifts the paper clip.

Test one change at a time

The challenge: which design lifts the most paper clips in 30 seconds? Test one variable:

Number of blades (2, 4, 6)
Blade size
Blade angle (how much they’re tilted)
Fan distance

Run each design three times, count the clips lifted and compare. Keep everything else the same.

What usually happens

More blades don’t always help. Too many can block each other, and too few catch less wind. The angle of the blades often matters more than anything else: flat blades face the wind and just get pushed, while angled blades turn. Results vary with your fan, so tell students to expect surprises.

What it tells us about real wind power

A wind turbine turns the kinetic energy of moving air into rotation, which drives a generator that makes electricity. The same ideas show up in real turbines:

Blade shape and angle matter a lot.
A steady wind is better than a gusty one.
Turbines need to be placed where it’s windy, so a wind farm needs wind data first.
The blades must be strong enough to survive storms.

It’s also a chance to discuss trade-offs: wind is clean and renewable, but it doesn’t blow all the time, and turbines affect landscapes and wildlife.

Safety

Keep fingers and hair clear of the blades, and use a low fan setting. An adult handles the skewer.

The full lesson is Can the wind power our school? in the Power Up: Where Electricity Comes From unit, alongside Where does our classroom’s electricity come from? and Why don’t we use solar power everywhere? Sign up for three lessons free.