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Today we are going to show you how to make a LEGO Balloon Powered Car. It is a fun STEM activity to do with kids teaching about the science of wind and also engineering!
I stumbled across a fabulous book at the library recently. I liked it so much that I ended up buying a copy for our home library. It is called If I Built a Car, by Chris Van Dusen. What I like about it is the creativity that it inspires in young minds.
This book inspired some fun car activities including our LEGO balloon powered car! (See more Storybook STEM projects)
The story is about a boy riding in the back of a car with his Dad. He tells his Dad that their car was OK, but if he built a car it would have all these amazing things like a snack bar, the ability to go on water, under water, fly, drive on autopilot, and more exciting things. It is such a fun story.
As soon as I read it to my kids they started telling me all of the fun things that they would put into a car that they built.
I teach a little “Five in a Row” book club at our homeschool co-op and it was my turn to teach last week. I knew right away that I wanted to use the book If I Built a Car for our lesson. It was fun to come up with some activities to go along with the book for the class. There are fabulous illustrations that make the kids just giggle.
After reading the book to the class, I loved hearing their minds go on about what they wanted to include in their cars that they invented. I gave each of the kids a little paper asking them what they would put in their cars. The back side was blank for them to draw their cars. They spent so much time working on these and it was wonderful to hear how creative they were.
Next in the lesson, I had some LEGO balloon cars built that use air pressure to push the car. This was so much fun and so easy to do. My kids have played with these over and over again at home.
Watch the video below of me reading this book & my son teaching how to build the LEGO Balloon powered car.
This is the first in my Learn ~ Explore~ Play series. You can find the series on my YouTube Channel. There will be many more to come!
How to Make LEGO Balloon Powered Cars:
To build these balloon powered cars, you just need to build a basic LEGO car.
You can use a pre-built LEGO car and add some bricks on top to hold the balloon in place on top of the car, or build your own with 2 sets of wheels.
To propel the car, blow up the balloon, then twist it a little to keep the air from escaping. Put it in between two little towers with a block on top to attach the balloon.
Give it a little nudge and the car travels balloon will propel the car!
If I Built a Car Snack
Finally we made a simple car snack with apple slices, toothpicks and grapes (or olives). Just slice the apples and put 2 toothpicks through each apple and attach 4 grapes or olives for the wheels.
I used grapes in the class, but at home my kids wanted to make them again with olives. These are yummy and healthy, too. I let the kids make them on their own and they loved it!!!
The Science Behind the Balloon Powered Car:
While this activity is tons of fun, there is a lot to learn from the balloon powered car! I love activities that teach, but are also just a blast. There are a few different elements in play here. We have engineering design, Simple Machines, and Newton’s Third Law of Motion.
First, the engineering aspect. We learned a few things as we built our LEGO balloon car about what works well and what doesn’t. The tower we built to hold on the balloon needs to be tall enough so the balloon is out of the way of the wheels. Also you need to make sure your balloon is facing the correct way to make the car go forward and not backwards.
The wheel and axle are examples of simple machines, this is a great project when talking about simple machines!
The car moves from the pressure of the air pushing out of the balloon. This is the energy of motion that Newton discovered. For every action, there is an equal and opposite reaction or force.
We also have an example of kinetic and potential energy. When you inflate the balloon, it stores potential energy. When you release the balloon, kinetic energy is in play.