Category Archives: Air Powered Racers

Air Power & Lego Racers Build It Workshop

Today’s workshop was so much fun.  We learned about Science, Technology, Engineering, and Mathematics using balloons and Legos.  Our focus today was to understand how air can be used as a source of energy to transport objects.

First of all, lets start with these two definitions:

        Power is the force, strength, or ability to do or accomplish something.  
                                                                (source: The American Heritage Children’s Dictionary pp. 567)

        Air power is the ability to move an object with air.

To demonstrate how air can be used as power, the first thing we did was to do experiments with balloons.  All of the kids were given their own balloon of a different color to use.  Balloons are able to hold compressed air.  We blew up the balloons with air we breathed out of our bodies.  You can also blow up balloons with air pumps, air compressors, and things such as helium gas tanks.

                    Air As Energy

                    Put your mouth on the open end of your balloon. 

                    Blow air your balloon.  

                    Pinch the end closed so no air escapes. 

                    What do you observe?

                    When the teacher says let it go, let go of the end. 

                    What happened?

                    Why do you think this happened?

The kids had lots of fun blowing up their balloons and letting them loose.  The balloons traveled all over the place.  They shot forward randomly and looped all around to the left and right through the air above us.  Compressed air escaping from the balloon was propelling the balloon forward, powering the balloon to travel randomly through the air.

                    Air Power Energy For Transport

                    Tape one end of fishing line or string to a table or chair.

                    Thread a straw onto the fishing line or string.

                    Tape the other end of the line or string to another table or chair.

                    Tape a balloon to the middle of the straw.

                    Blow up the balloon and pinch the end closed so no air escapes.

                    What do you observe?

                    Starting near one table or chair, release the pinched end of the balloon.

                    What happened?

                    Why do you think it happened?


Instead of allowing the balloon to travel at random, we can control the direction of the balloon by attaching it to an object. 

Tie a string onto a solid object at one end of the room.  Tape a balloon to a straw.  Thread the straw onto the string. 

Tie the other end of the string to another solid object. 

Fill the balloon with air.  Pinch the end of the balloon to hold the air in.  When ready, let go.  The balloon will travel along the straight line of the string.

The straw and string provide control and guide the balloon as air power propels it forward. Other examples of guiding objects in real life and controlling the direction of a moving object might be: a bullet traveling through a gun barrel, or a vehicle at an automatic car wash. The vehicle is put in neutral when it’s wheels are placed on a track at the car wash.  The rails and track guide the vehical to travel forward in one direction.  Can you think of more examples?

The Lego Building Challenge

Use air as power to transport a Lego Race Car.

The kids were divided into three teams.  They followed blueprints to build three different Lego race cars from Lego Racers kits.

The cars have a special hard plastic chamber that receives air that has been compressed by a plunger.  The chamber connects to the plunger. The plunger is a flexible plastic “accordion” type hollow device.  The walls have folds that are flat but when compressed they fold like an accordion.  When the plunger has been compressed, it sends compressed air into the chamber on the car.  When the chamber on the car is full of air, the force causes it to shoot forward and disconnect from the plunger.  The compressed air converts into energy to push the car forward.  You can read more about the science involved in this in another story located here.

Math Connection


Place the finished car on the floor.  Connect the chamber of the car to the stomper.  Sit on your knees and using your hands stacked together, palms flat, stomp the stomper with the force of your hands.  You can also use your foot to step on the stomper, however it is more difficult to control your applied force and some kids find this action more difficult than using their hands. The Lego Racers car should shoot across the floor when the stomper action is applied. 


Using a measuring tape, measure the distance the car traveled.   Record your distance in the chart below.   Repeat this process 2 more times for a total of 3 measurements.


Record Distances & Find The Average

Team 1









Average Distance



Team 2









Average Distance



Team 3









Average Distance



Find the AVERAGE distance traveled by adding the three distances together and dividing by three.

___________ + _________ + ______________= _______________  divide by 3 =_________________

Race 1 + race 2 + race 3 = combined totals divided by 3 = Average distance

Write your average distance on the chart above.


Re-engineer or modify design:

Now modify the car if desired and repeat the process above.  

What did you modify? 

Did the car go a longer or shorter distance?  


How far did it travel?

All the pictures from today are in the video below.  I hope you will take a look at our video and enjoy our fun learning adventure.  It is so much fun to learn with hands on projects like this.

The kids were given packets with lots of learning material to take home and further their learning.  It should keep them busy for a couple more weeks of learning activities.   The packet included: 
                Math Connections
                Science Connections
                Technology Connections
                Engineering Connections
                Geography Connections
                Research Connections
                Writing Connections
                Arts & Crafts Connections
Internet Links for further study
                Field Trip Ideas
                Coloring Pages
                Vocabulary Words

This was absolutely one of the funniest learning units I have ever put together. I just love using Lego’s to teach the kids.  Check out this 5 minute video about our fun Build It Workshop.

No kidding, there really is such a thing as an airpowered car.  Check out the AIRPOD car powered by fresh air.  It was developed in France, and will be marketed in Asia according to the article.  Here is a wikipedia explanation of a Compressed Air Car.  Various companies have been developing air powered cars since 1999 and they have been available to consumers since 2002.  Even Honda has an airpowered car that came on the market in 2010. 

I am amazed at the inventions and progress in technology of products to create a greener world with less harmful effects by reducing some of the use of burning fossil fuels.  Before researching this topic, I did not know there was an actual car on the market you could drive that was powered by air.  You may soon see air powered cars available in car lots near you, right next to other “green” technology vehicles like electric, solar, and others.  For sure this new generation of kids will see such technology available in their lifetime.

If you would like to help us in our fundraising efforts to support our 4H club.  Please see the information posted here at FUNDRAISER.  Be sure to read all of our 4H Lego and Robotics Academy stories.  Check out our 4H Build It Workshop stories too.   Thanks in advance for any donations you can give to help our 4H kids reach their learning goals.

This story will be linked up with
No Time For Flash Cards
Science Sunday
Raising Homemakers
Sharing Time

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