Turn current on, and magnetic field is on. Current off and magnetic field is off. Disconnect battery and compass deflects back to rest. The most familiar example is the junkyard magnet that picks up cars and drops them on top of a stack. Award magnets as prizes.
Electric motors use current to set up two magnetic fields.
These fields are set at right angles to each other. Building a Motor Using the kit provided, follow the instructions, and build the motor. Kits are from a catalog. All you have in you pocket are four fairly strong magnets and some string. Then sold the magnets and began a new life.