Blast Off! An Easy DIY Science Experiment for Kids: The Paper Cup Rocket

I’m Ken Kuwako, a science trainer. Every day is an experiment.

Do you know about a special ‘flying experiment’ that the whole family can enjoy? All you need are cardboard and paper cups that you have at home. No special tools are required. You might be surprised and think, “Huh? Can it really fly?”, but it really flies high and feels great! Now, let’s try to make this magical rocket!

It’s Just That Simple! How to Make a Magical Rocket

The star of this show is the paper cup rocket. It’s super easy to make, and you can start right away with your kids. You only need these materials!

Paper cups

Cardboard box

The process is simple. First, cut a circular hole in the cardboard box that is slightly smaller than the diameter of the paper cup.

Gently place the paper cup over this hole, and your rocket is complete.

In this state, gently tap the side of the cardboard box, and…

Whoosh! The paper cup will shoot high into the sky. As shown in this video, it’s always fun to watch it fly with such force.

Why Do Paper Cups Fly? Let’s Look at the Power of Science!

So, why does the paper cup fly just by tapping the cardboard? The secret lies in “air.”

When you tap the cardboard, the air inside the box is compressed and tries to rush out of the box all at once. At this moment, the air, along with its ‘friends,’ rushes out of the small hole with all its might. It’s like a lot of people all rushing out of a narrow doorway at the same time.

This powerful flow of rushing air is called an “air cannon.” You may have done an “air cannon” experiment before, using cardboard or a paper tube to shoot smoke rings. This paper cup rocket also uses the power of the air cannon.

The air rushing out of the hole pushes the paper cup up from below, like a rocket, causing it to fly into the air. There’s actually a little trick to this experiment, besides just tapping.

It’s to push down on the center of the cardboard with your whole palm in a gentle, ‘fluffy’ motion. This allows you to push the air inside the box out more efficiently, making the paper cup fly higher and farther.

The Wonders of Science You Can Do at Home

There are many interesting things around us that use the power of air. For example, a balloon inflates using the force (pressure) of the air inside it trying to expand. A water gun uses the force of compressed air to powerfully push out water. This paper cup rocket is a wonderful science game that lets you see and feel the power of air.

You might struggle a bit to get it to fly at first, but it’s also fun to try and figure out together with your kids how to make it fly higher or straighter. This small experiment might spark a sense of wonder, making them love science even more. Please, experience the joy of science together as a parent and child.

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