This is the kind of energy most people think of when you mention ‘alternative energy’, and for good reason! Without the sun, none of anything you see around you could be here. Plants have known forever how to take the energy and turn it into usable stuff… so why can’t...

Do you like marshmallows cooked over a campfire? What if you don’t have a campfire, though? We’ll solve that problem by building our own food roaster – you can roast hot dogs, marshmallows, anything you want. And it’s battery-free, as this device is powered by the...

We’re going to learn how to build a weather instrument that will record whether (weather?) the day was sunny or cloudy using a very sensitive piece of paper. Are you ready? You can use sun print paper to test how well your sunblock works – just smear your favorite...

This experiment shows how a battery works using electrochemistry. The electrons inside the copper are going to react with the acid in the lemon juice to make a flow of current you can detect with a digital multimeter. The copper electrons are chemically reacting with...

We're going to launch a rocket by building up pressure using a chemical reaction. I really like this experiment because it combines chemistry, gas pressure, and Newton‘s laws of physical motion all in one cool experiment. For every action, there is equal and opposite...

Mathematically speaking, this particular flying object shouldn't be able to fly. I mean, it doesn't even look like an airplane! There are endless variations to this project, including changing the size and number of loops. You can even tape two of these together for a...

Want to build a kite in less than 5 minutes? This kite is basically a paper airplane on a string. It’s fast and easy to make. The best thing about this kite is that it needs next to no wind to get airborne, so you can simply run with it to get it up in the sky. Why...

This is a double-project, because each requires the scraps of the other. The origami airplane requires a square sheet of paper, and the ninja star needs the strip left over from turning a regular sheet of copy paper into a square sheet. Both of these contraptions fly...

A cable car transports people or things in a vehicle that uses a strong cable to pull at a steady speed. Also called aerial lift, aerial tramway, or gondola, these are different from the cable cars associated with San Francisco, which use buried cables to move the car...