Make your own Compass
Fascinating Food / Feel the Force

With little more than a needle and a magnet.

Suitable for ages 7- 14


Compasses are essential pieces of equipment for anyone trying to find their way around our planet, whether on the surface or deep underwater. If you buy one from a shop it will cost you a few pounds at least, but you can make your own for next to nothing, as long as you have a magnet handy.


• One sewing needle
• A small bar magnet. A fridge magnet may even work if you’re stuck

• One small round piece of cork (A salami style slice off a wine cork is ideal)
• One small glass or bowl with water in to float the compass on at the end




• Find the North end of the magnet, if you can. Run this end of the magnet over the eye end of the needle sixty times – each time rubbing it away from the sharp end. If you don’t know which way North is, don’t worry, just choose one end and use that.

• Now stick the needle through the piece of cork. If you’re using a slice of a wine cork, stick the needle through the circular part from one rounded edge to the opposite. Perfect!.
• Place your compass in the water, and make sure there is no metal or other magnets nearby. The sharp end of the needle should swing around to point to magnetic North.
• (If you didn’t know which end of your magnet was which, you have a 50% chance that you have magnetised your needle so that the eye end points North. You could use a map to check this.)


The Earth’s magnetic field may be weak, but it’s strong enough to exert a force on magnetic objects within it.

The needle became magnetised when you rubbed the bar magnet over it – the eye end became a south pole and the pointed end became a north pole

Putting the needle in the water allows it to move freely and orientate itself towards magnetic north. Check it out with a ‘real’ i.e. paid for compass.


If you’re supercool, you can use a piece of paper to float the needle on instead of using the cork. Put the paper onto the water surface first, then place the needle on top.

If you are extra supercool you could use rice-paper to float your needle on. After the rice-paper has become soggy and sunk to the bottom, the needle will float on its own, supported only by surface tension…


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