How To Make A Compass

Here’s how to make a compass at home or in the classroom. Learn what a compass is and how it works. All you need are a few simple materials to get started. We love fun, hands-on STEM projects for kids!

What is a Compass?

There are magnetic rocks on earth called magnetite, which actually means magnet mineral. Ancient scientists found that they could use magnetite to help them make a compass.

A compass is just a magnet that always points to the Earth’s North Pole. It is helpful for navigation, whether walking in the wilderness or sailing a ship. A compass and a map can show where you are and what direction you need to go in.

How to Make a Compass

The Earth is a giant magnet with a unique magnetic field. In this activity, you’ll build your own compass to explore how Earth’s magnetic field affects objects. You create a simple compass by magnetizing a needle and floating it on water. The magnetized needle aligns with the Earth’s magnetic field, and one end will always point north!

Recommended Grade Level: 3rd-5th Grades

Supplies:

Small Bar Magnet (refrigerator magnets work!)
Sewing Needle
Plastic bottle cap
Bowl of water
Printable Instructions Below

Instructions:

STEP 1: Turn the needle into a magnet by rubbing it along the surface of the magnet about 60 times.

💡 Be sure to rub the needle in the same direction every time. Pretty soon, the needle will become magnetic, too!

STEP 2: Lay the needle on the rim of a plastic bottle cap.

STEP 3: Carefully float the bottle cap in a bowl of water so it is free to move around.

The needle slowly turns the bottle cap around until it points to the North Pole!

💡 Please note: if it does not work, rub the needle with the magnet again.

How Does a DIY Compass Work?

Earth’s Magnetic Field and Magnet Poles

Did you know that the Earth is like a giant magnet? Just like any other magnet, it has two poles: a North Pole and a South Pole. The Earth’s magnetic field stretches between these poles and is similar to the magnetic field you might see around a bar magnet.

Comparing Earth’s Poles to Magnet Poles

Bar Magnet: A bar magnet has a north pole and a south pole. Opposite poles (north and south) attract each other, while like poles (north and north or south and south) repel each other.
Earth’s Magnetic Poles: Earth’s magnetic North Pole and magnetic South Pole work the same way! When you make a compass, the magnetized needle has its own north and south poles. The needle’s north pole is attracted to Earth’s magnetic South Pole, which is near the geographic North Pole. This is why the north end of the compass needle points north!

When you make your DIY compass, the needle you magnetize acts like a little bar magnet. The north end of the needle is drawn to Earth’s magnetic South Pole (near the geographic North Pole), and this is what makes the needle align with the Earth’s magnetic field.