The first compasses were made out of lodestone, a magnetic rock. When floated in a bowl of water, the lodestone would work like a magnetized needle, pointing north and south. Lodestone is magnetite, a volcanic rock, and was formed with its composite minerals aligned with the magnetic north and south poles.
You can make your own simple compass using household items.
1. First, magnetize a needle by stroking a bar magnet several times from the needle's eye to its tip. Don't rub the magnet back and forth across the needle. Once your needle is magnetized, stick it lengthwise through a thin piece of cork (use the top 1/8-inch of a wine cork, if you have one).
2. Set the cork and needle in a nonmetallic bowl of water, and watch what happens. The needle should turn so that it faces in a north-south direction. If you have another compass, use it to check the accuracy of your magnetized needle.
You can use a homemade compass, or a regular one, to combine an orienteering activity with a nature study. This is a fun opportunity for the whole family to learn how to find directions and draw a simple map and at the same time observe flora and fauna (plants and animals). If you live within easy traveling distance of a forest or a grassy area along the ocean or a lake, that place would be ideal for this project. However, it can also work in a city park or a backyard.
1. Find an area that you would like to work with. Use a compass to find magnetic north, which will be accurate enough for this project.
2. Once you've found the right direction, mark off a square with sides ten paces long: mark the starting point and go ten paces due north, then ten to the east, ten south, and ten paces west, using sticks or rocks to mark the corners.
3. Use guidebooks to identify the plants within the square (younger children might do best just identifying trees, while older children would enjoy the challenge of trying to identify all of the plants in the square, as well as any animal tracks or droppings).
4. Record all of your findings on a map, making sure to mark the directions and represent the square. Mark any highlights or information you would like to remember.
For more information about compasses and navigation, check out our Finding Your Way with a Compass Teaching Tip.