Goal: Make a needle point north.
You will need: a sewing needle, a magnet, a small piece of cork and a bowl of water.
Step 1. Stroke the needle with one end of the magnet about 30 times, always in the same direction.
Step 2. Push the needle carefully through the piece of cork.
Step 3. Float the cork in the middle of the bowl of water.
Step 4. Wait for the needle to stop turning.
Step 5. Check which way it points against a real compass or a map.
Tip: Keep other magnets and metal away, or the needle will point at them instead.