Simple Machines: Wheels and Axles (and gears)

I guess I didn't take any pictures of our wheel and axle activities, but I'll include a few links.

First of all, I thought it was interesting to think of a wheel as simply a type of lever—one that rotates around 360 degrees. This video I mentioned on the Screw post, plus this other video about wheels, were really entertaining and informative.

This page is full of good ideas for wheel-related activities. They also made a waterwheel, which is something we did during our water unit a few years ago. It's really fun.

We chose to study gears along with wheels, and here are some gear activity ideas.

Another gear video.

We also talked about ratios and how they relate to gears.

And just in case you've ever wondered what the difference is between a gear and a sprocket, you can find out here!

To show how wheels can help you measure things, we made surveyor's wheels or measuring wheels, sort of like these described here.

We looked at the gears on our bikes and noticed how, just like with levers, increasing the size of the spokes or pedals can change your mechanical advantage.

We watched a couple videos about how wheels are even used in the natural world! For example, these rolling salamanders and caterpillars use the principle of the wheel to escape from danger.

And these leaf-hoppers actually have microscopic gears to ensure that both their legs spring at the exact same time when they jump. Amazing!!