You will need:

•  a board or tray at least 40 cm long and wide
•  marble(s)
•  a selection of card

(cereal boxes or heavier card will be fine)
•  scissors
•  sellotape
•  a partner or two
•  an adult to help with cutting
•  a watch

Lean your board against a book or two, like a ramp.
Hold a marble at the top of the tray and let it roll down to the bottom.

Change the angle of your tray until the marble rolls down, without stopping, as slowly as possible.

It’s fun watching the marble run down the board, but it’s all over too quickly. It’s possible to change the surface of the tray so that your marble takes ages to get from top to bottom.

One group of children made changes to a large tea-tray (you probably have one like it at home) so that a marble took almost 30 seconds to go from the top to the bottom.
How did they do it?
Go to the next page to find out.

The children cut and folded long pieces of card and sellotaped them to the tray to guide the marble in a zig-zag manner.
From overhead, their tray looked something like this.
The arrows show the direction in which the marble travelled

Of course, one end of the tray had to be higher than the other in order for gravity to pull the marble.
If there wasn’t enough of a slope, the marble would stop. But the children didn’t want to have too much of a slope either so that the marble would move as slowly as possible.

Could you design and make a marble-run like this?

1. Explore the materials.
Discuss these questions with your partner(s).

•  what kind of card do you have?
•  will it be strong enough to hold the weight of the marble?
•  will you need to fold it?
•  will it be easy to cut it with a scissors?
•  how are you going to attach your card wall to the tray/board?

You will have a lot of cutting, sticking and testing to do. Plan the work on the next page.

•  describe the different stages of the work.
•  who is doing what?
•  how long will the whole thing take?

•  what’s your slowest time?

Did you use any materials that weren’t on the list on page 1?
List them here and explain why and how you used them.
 

Were you happy with the materials you used?
 

Would you use different materials if you were going to do this again?
 

Did you work well as a team?
 

What part of the work did you enjoy most and why?

To think about…

• what other type of marble-run could you design and make?
• if you were having a marble-run competition with your friends or with your class at school, what things would you have to keep the same to make the competition fair?