Students are introduced to the idea of designing and making a car that uses a balloon as its energy source. They are challenged to think about how a balloon car would be similar to a wind-up and how it would be different. Next, they create concept drawings and materials lists for their balloon cars. Finally, they begin their balloon cars.
Show the class a balloon. Blow it up and then release it. Ask:
Ask students to think about how they could use a balloon to make something similar to a wind-up:
* Earlier, we made wind-ups. What made them go?
* How could you make a car that uses a balloon as its energy source?
* What materials would you need?
Planning a balloon car:
Introduce the materials for the car: spin a wheel on a skewer (axle); name the cardboard the “car body”. Tape the large straw to the balloon and blow the balloon up with the air pump and identify the masking tape and rubber bands as ways to hold everything together. Distribute the Worksheet “My Balloon Car” for students’ initial planning. Give students materials only after they have an initial plan.
Starting to make balloon cars:
Provide each student with 4 wheels, 2 skewers and a cardboard rectangle. Give tape and rubber bands to each group. The first task is this:
Make a car that rolls easily and straight.
Here are two videos. The first shows a variety of car bodies. The second shows how to make a basic car. Allow students to experiment with the materials, and record any problems that come up. Here are videos of some typical issues and possible fixes: