Go! My girls and I have had a great time making and racing these cars. In a moment show you how to make a basic one. One of the things I love about these cars
is they work just like a rocket. The air comes out the back and it pushes
the vehicle forwards. Lots of things work like that. When a
bird flaps its wings, what the bird is doing is pushing down
on the air, and that makes the bird lift up. Now, you can’t fly because you’re too heavy, and, you know, you don’t have wings! But you might be able to swim. If you swim, and go into the water, if you
do the breast stroke, when you push backwards on the water that makes you go forwards. It’s just the
same as for the rocket when hot gases come out the bottom of the rocket they push it upwards. With the balloon racer, the air in the
balloon goes through the straw and is shooting out backwards. That pushes the whole balloon and
the car in the opposite direction, which is forwards. Crash! So what you do, is blow through the straw… …and then, what do you think is going to happen when I let go?
It’ll move! Which direction? That way! Making and racing balloon cars is a great way to get children thinking like scientists and engineers. Handling the different bits and pieces used to make the cars gives
children an opportunity to think about the properties of materials. Trying to make the cars go faster or
further challenges them to solve problems and think how changing one thing affects another. This is your basic model balloon car and it’s really easy to make. I’ve got everything I need in front of me here. Two straws, which are going to be my axles, and this piece of cardboard is going to be my base. The first thing I do is Sellotape my axles to the base of my vehicle. Tape that on there, and another bit of tape here. That’s my axles on the bottom of my cardboard. Now I need to affix my wheels. I’m using these wooden kebab skewers – you can see that I’ve trimmed the length down. For the wheels I’m using these green
milk bottle lids. The really good thing about these lids is these skewers go through them really easily and they also seal on it as well. They stick well. That’s one, And make hole in the other one, and push it through. And put that one on there, and push that through the straw, and there’s my other wheel. There you go, there’s one. For the other one, exactly the same. So there’s my vehicle, and as you can see, it rolls backwards and forwards. Now I’ve got to put the engine on! What I’m using is this balloon, and a straw. The good thing about this straw is it’s bendy, so I can tilt it up. What I’m going to do is connect the balloon to my straw with a bit of masking tape. Put the straw in, and now I have to tape my engine to my
vehicle. You have to do it so that you’ve got the end of your pipe
hanging over the end of your car. I’ll tape it on with a bit of masking tape. One, and two. There we go. Now all I’ve got to do is start the engine! Three, two, one… I knew it! Bash! Who’s went further? Me! And which one went faster? Mine! Are you sure? Yes! Do you think we should have a race and see? Yes! Three, two, one, go! Mine went fastest! Mine went slower second time. Do you think it was faster the other time? Yes, definitely faster! Shall we try it again, best of three?