magnet and a paper clip. place the magnet on a smooth surface. place the paper clip on the same surface and show your child how to play with it to see how close to the magnet you have to put it to demonstrate the magnet’s pull. measure that distance. that becomes your control.
next help your child experiment with putting items between the magnet and the paper clip. try paper, cardboard, aluminum foil, wood, and the blade of a kitchen knife. do you have to place the clip closer before it will react to the magnet? how much closer? show your child how to record the results.
what materials seemed to block 