# How to make a marble run

#### Beat our timed challenge by building the ultimate marble run!

Before you begin…

If you’re under 18, make sure you have an adult with you.

#### 1. Create the box

First you will need to find a cereal box no more than 60 centimetres high and 40 centimetres wide. Close the top of the box and seal it tightly with tape, then carefully cut the front off the box to create what will look like a tray. If you don’t have a cereal box the right size you could alternatively cut pieces of corrugated card to the right size and glue them together.

Next you will need to make a stand for the back of your box in order to hold it at a slight angle – this will ensure that your marble keeps rolling down your run. Now carefully cut the top off a plastic bottle and cut a circular hole in the top of your box so that the top part of the bottle can slot into it, like a funnel. This is where you will place the marble.

#### 3. Form the run

Now the challenge is to get the marble to travel from the top of the box to the bottom in as close to ten seconds as possible. To do this you will need to make a track down the box for the marvel to follow. Cut strips of card, kitchen rolls and more funnels to create a run, then try out each section by taping it with masking tape before glueing it on.

If the marble is travelling too fast down certain sections, try using different surfaces on the strips within your run to see if they slow it down at all. You can stick sandpaper in, for example, or add some small bumps of card to slow it a little. You could also try adjusting the angle of some of your strips of card too – does that make any difference?

To complete your run, carefully cut off the bottom of a plastic bottle and place it at the bottom of the box to make a marble catcher. Now get a stopwatch and time how long it takes for the marble to get from the top of the box to the bottom. How close were you to ten seconds? If it’s too fast, or too slow, try adjusting your run again to see if this improves the time.

Summary…

Gravity pulls the marble down the run. If you let it fall freely, it would take less than a second to hit the bottom. By adding strips of card you are making it travel further, stop and change direction, therefore slowing it down. Rough or bumpy materials will make it even slower.

Disclaimer: Neither Future Publishing nor its employees can accept any liability for any adverse effects experienced during the course of carrying out these projects or at any time after. Always take care when handling potentially hazardous equipment or when working with electronics and follow the manufacturer’s instructions.

For more science and technology articles, pick up the latest copy of How It Works from all good retailers or from our website now. If you have a tablet or smartphone, you can also download the digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, subscribe today!