Everyone is familiar with magnets; they grace the doors of refrigerators everywhere. But beyond the refrigerator door, just what does a magnet stick to? What material properties make a magnet seem magnetic?

The Magnets experiment involves a steel tray, a set of differently shaped permanent magnets, and an assortment of small objects, some which the magnets will stick to, others not. In determining the reasons why magnets do or do not stick, most students will easily rule out the wood and plastic pieces as non-magnetic, and some of the metal ones as clearly having magnetic properties. However, some metals, like aluminum or copper, do not have strong magnet-attracting properties, although they appear to have similar physical properties to those that do, usually steel alloys or raw iron.

Ask students to sort the objects into two groups: those that stick to magnets and those that don’t, and have them explain some similarities between members of each group.