Blow down the tube and make a pea float in the air!

Please download the pdf instructions for an up to date version.

Making the toy

1. Block one end of a tube. Bamboo has useful blocked joints but other tubes will need a good stopper to make sure no air gets out,- for example, a piece of a plastic bag can be tied on to the end.

2. Make a circular hole about 4mm wide near the closed end of the tube, using a bradawl.

3. Find a pea or make a small, light, ball from chalk or dried chewed paper. It must be quite round and even.

Playing with the toy

Place the ball in the hole and blow gently. The ball will rise up and be held in the air.

See how long and how high you can get the ball!

Problem solving

a) The ball flies away.

You may be blowing too hard, or the hole is too small.

b) The ball won't stay in position.

The air from the hole is not even: smooth the sides or use a larger diameter tube.

Or the ball may not be round (spherical) enough.

c) The ball won't stay up for long.

The hole may be too big, or the ball may be too heavy. Or you just may not have enough puff!

Developing this toy

Change the length of the tube or try different diameters.

Make the hole smaller and try a smaller ball.

Make an umbrella to catch the air.