The cold facts about squeezing a lot into a little. See how a little hot air can make a lot go a long way, and before the end of the Programme some of the audience will get blown up! So, sit down and find out how, with a bit of inflation, you could be on the move. Meanwhile - Think of a Number - squeeze six marbles into a matchbox and divide them between three boys and three girls so that each person receives a marble but one marble remains in the box.

The people who thought nothing was something - the man who invented nothing. People who have managed to sell us nothing. How can you measure nothing ? And how the force of nothing keeps things up and holds us together. So if you have nothing on, except BBC1, discover that there's more to nothing than meets the eye. Meanwhile - Think of a Number - Quickly multiply this... it takes no time at all. 1x5x8x3x4x0x9x6x7x2

Faces - old faces, new faces. Pulling faces and painting faces. Discovering that looks are more than skin-deep. See the woman who has at least 60 faces and find out how a face can get you anywhere. So prepare to face the fact that you may not be able to face yourself in quite the same way again. Meanwhile - Think of a Number: two faces - father and son - when the father was 31, the son was eight. Now the father is twice as old as the son. How old is the son now ?

Reflect on the speed of light and the colour of space. Why Father Christmas is never seen. See what your screen looks like in black and white, red, blue and green. A solar plane that could reach new heights and how you could ride on a sun-beam for free... So if you don't want to be in the dark switch on to see the light - from infra red to ultra violet. Meanwhile - Think of a Number - it's all relative! If 2 is company and 3 is a crowd, what are 4 and 5?

Computers - digital computers, electrical computers, wind, steam and sun computers. Computers that talk and computers that draw. Plus an invitation to knock about the oldest computers known to man. Meanwhile - Think of a Number: spot this one without the aid of a computer! What arithmetical symbol can you or a computer use between 2 and 3 to make a number larger than 2 but less than 3 ?

Seeing how the problem of Cleopatra's Needle was sewn up, how to pull your weight and someone else's besides. See a tailor-made jacket that weighs 25,000 tons, which turns out to be a bit of a drag, not to say boring. So, mechanically speaking, it could be to your advantage to watch; even a moving experience. Meanwhile - Think of a Number - get a move on with this! Make eight 8s and a few plusses move about to make a 1 and 3 zeros.