Various bits of U.S. change (dime, nickle, etc.)
Some sort of U.S. paper money (1 dollar bill, 5 dollar bill, etc.)
A fairly strong magnet
1. Ask yourself, which form of American currency is magnetic, penny, nickle, dime, quarter or a paper bill?
2. Try the different forms of money. When you try the paper bill you probably need to hang it over a table edge. It needs to be able to move easily and freely.
Were you surprised? The coins have no metal in them that is attracted to a magnet. The bills however do! The ink in U.S currency contains iron which is attracted to magnets! Now that you know the secret, go ask your friends. See if they get it right!
For more about magnetism check out the magnetism lesson plans.