Fun at Home - Air Powered Car

Air Powered Car

For this activity we are taking the tried and tested method of creating a balloon powered car, but we want to incorporate a Design Thinking Process so that young designers and engineers can really start to make predictions, observations and extend this activity by adding variables to the mix. The first thing we will do is construct our balloon powered car and test it, making some observations as we go. Then it’s up to you to try different designs and problem solve at home.  Although we’ve included some steps to follow it’s important that you try your own solutions. Don’t be disappointed if your design doesn’t work first time and you make changes as you go along, that’s all part of the design process and demonstrates that you are learning.

Time to do and skill level

20 to 30 minutes, this activity can be extended if you want to experiment with different materials, car designs and track surfaces. 

Easy – younger children may want some adult help with scissors or skewers

You will need:

You will need

  • Design Thinking Process PDF - PDF download
  • Balloons
  • Pencil and compasses
  • Scissors
  • Sticky Tape
  • Wooden skewers or dowel
  • Paper
  • Drinking straws, cardboard or plastic
  • Wheels  
  • Cardboard for chassis
  • Smooth hard surface as a test track


Step 1 - Check your equipment list and print off your Design Thinking Process or have it on screen.

Design Thinking Process


Step 2 - Create your chassis but cutting a rectangle out of card, this one is approximately 10cm x 24cm. You can use any rigid cardboard, thin plywood or even a base plate from a modular brick system. A rigid chassis is best as a wobbly base will cause the car to lose more energy as it travels.

Create Your Chasis

Step 3 - Cut two straws to house your axles, make them the same width as your chassis and fix them to the chassis with sticky tape. If you have a look at the picture you can see they should be attached parallel to each other and as perpendicular to the centre line of the chassis as possible. Don’t worry if yours are not perfect but observe how your car behaves and be prepared to refine your design.

 Air Powered Car - Step 3A Air Powered Car - Step 3B

Step 4 - Take one balloon and cut the mouthpiece off the end, this thicker part of rubber would make it more difficult to attach your balloon to the straw exhaust.

Air Powered Car - Step 4

Step 5 – Take one plastic straw and insert approximately 2cm of it into the mouthpiece of the balloon. Now wrap the balloon securely around the straw with sticky tape.

Air Powered Car - Step 5

Step 6 – Use sticky tape to fasten your plastic straw exhaust to the chassis of the car. Before you stick it down practice at inflating the balloon, have you left enough straw hanging over the edge of the chassis?

Air Powered Car - Step 6

Step 7 - Cut two wooden skewers slightly longer than the straws, these skewers are the axles for the wheels. 

Air Powered Car - Step 7

Step 8 – To make your wheels cut four circles from cardboard and carefully make a hole in the centre of each wheel with the point of a wooden skewer. Attach one wheel to a skewer before sliding into the straw axel and attaching the second wheel. Test and see if your axle spins freely. This is one of the stages where you will lose a degree of accuracy and probably end up with wobbly wheels that need slight adjustments. If you have some wheels that exist already from a toy car or Lego, then try them.

Air Powered Car - Step 8

Step 9 – Hold the car up to your mouth and inflate the balloon by breathing through the exhaust straw or use a balloon pump. Pinch the exhaust straw to stop the air escaping until you are ready. Place the car on the ground and let it go.

Extension activity

Now that you’ve tested your car once you’ve been able to make some observations about how it travelled, and you can begin the process of refining the design or changing the variables. Here are some examples to try. You should record the difference each one makes.

  • Change the size of wheels, either a bigger/smaller circumference or narrower/wider tyres with more contact on the ground
  • Inflate the balloon less and see how far the car travels now
  • Use coins to add weight to the car, adding one at a time see how much weight you can transport
  • Extend or shorten the length of the chassis
  • Adjust the test track by incorporating a slope either up or down and see how it impacts on the trave of your car
  • What happens if you make the opening of the exhaust bigger or smaller?


What designs did you come up with? Take a picture or video and share on Instagram hashtag #museumofthegreatsouthern or Facebook remembering to tag us.

This Fun at Home activity is presented by:

Museum of Great Southern Logo