Simple experiments designed to determine which objects are magnetic can help children understand basic magnetism. One such experiment, designed by the BrainPOP Jr. website, is called "Gone Fishing" and shows children which objects are magnetic. Place several items such as a cork, paperclip and scissors into a box. Give the children a magnet and ask them to determine which of the objects are attracted to the magnet. This can be entertaining for young children as they watch the magnets lift and stick to the magnetic objects. As a result of their underlying structure, most metals are magnetic. Some objects, such as cork, for example, have an equal amount of positive and negative charge, meaning they aren't attracted to a magnet.
A cork and a magnet are commonly put together to create a homemade compass, and many different experiments can be done relating to this. Demonstrate an experiment to the children to avoid any possible accidents with the needle. Rub a magnet against a needle to magnetize it. This process could take awhile, so be patient. Take a small piece of cork and shove the magnetized needle through the center of it. Fill a cup with water nearly to the brim, and put the cork and needle in the water so the needle is floating. Make sure there is enough water to keep the needle in the middle of the glass. The needle will point to the North Pole of the earth, serving as a compass. The charged particles already within the needle (which make it magnetic) are arranged into “groups” by the action of the magnet. The magnet teaches the needle to behave like a magnet. The earth also has poles in this way, which is why compasses work.
One other way to make a compass uses a pencil, a block of wood, two magnets, and a circular bit of cork. Hold two magnets close to each other so two sides attract. In this arrangement, tape them to opposite sides of a circular piece of cork. Moving freely, this will now behave as a compass. Stand the pencil up on the wood, with a little help from some glue or tape if required, and balance the cork on top of it. One magnet will point north, and the other south. You can also do this by suspending the cork and magnets from the ceiling using string.
This experiment is set up in the same way as the floating compass experiment, but filling the glass to the brim isn't necessary. Instead of letting the earth's poles attract the magnet, use another magnet to see how the needle is affected. You can pull the tip of the needle around in circles, or by turning your magnet around, you can even repel the matching side of it. This can help kindergarteners understand more about how magnets work, including the idea that a magnet has a certain range dependent on its strength.