LEGO Balloon Car

Are you ready to make something really cool with your kids? Your children will go nuts over this fun, easy-to-make Lego Balloon Car. This balloon car is such a fun physical science experiment to try with preschool, pre-k, kindergarten, first grade, 2nd grade, 3rd grade, 4th grade, 5th grade, and 6th grade students. All you need are a few simple materials to try this fun stem project for kids. Ready for an epic balloon activity for kids?

Lego Balloon Car

My daughter loves making and creating with LEGOs. She is not one that can do it for hours, though. But when she has a purpose, she loves making and creating. One thing that she responds well to, though, is movement. If she can make a LEGO car actually move, without touching it, she would be so happy. I told her I could make that happen. So we made this Air Powered Lego balloon car. This is a fun science project for preschoolers, kindergartners, grade 1, grade 2, grade 3, grade 4, grade 5, and grade 6 students.

Now granted, this isn’t a constant movement, but it will get it started. It does move without being pushed.

Looking for more fun science activities? We have lots to choose from! Try our color changing flower experiment, the amazing leak proof bag, fun coke and mentos experiment, and DIY light bulb experiment.

balloon powered lego car

To start with you only need a couple simple supplies: any color balloon (without any holes in it) and a handful of Lego bricks to you can make into a car – so you’ll want some sort of wheels.

We made this simple, two wheeled wagon. A car, truck or anything with wheels will work, she wanted to use her princess wheels and those are for the wagon and we only have two. So here we are.

Next, we built up and created a small hole that the end of the balloon could fit through. It does not need to be super tight, so that air can flow through, but it does need to be tight enough to keep the balloon connected to the vehicle.

balloon lego car

When the vehicle is built, blow up a balloon, but don’t tie it. I twisted it quite a few times to give us a little head start and time to put the balloon through the hole without letting air out. The more air in the balloon the better. Or rather the farther the car will travel on it’s own.

Once the balloon was twisted and put into the hole on the car, we counted down from 5. When we got to “GOOOOO” I let the balloon go. You could see it twirling, letting the twist out. As soon as the twist was out, the air started flowing out of the balloon and the car moved. It moved fast too.

how to make a balloon car

It was super simple to repeat the process. We tried it, starting on the top of a hill. This helped give the vehicle extra momentum to be able to go down the hill farther and faster! That was super cool.

The reason this is so fun is of course because there is science behind it. The Law of Inertia is Newton’s first law. It says that an object will stay still, not moving, until an outside force moves it. The same goes for an object in motion. It will stay in motion until something stops it.

lego balloon powered car

In this case, the object (the LEGO vehicle) is stopped and will remain stopped until the outside force (air in the balloon) moves it.