Each colored plastic marble has a magnetic north and south pole allowing students to attract and repel the marbles while being challenged by the 3D effect of the magnetic fields. You can string the marbles together, build shapes and structures, or do variations on traditional magnetic demonstrations. They are great fun! Package of 20 comes in a reusable container. Marbles are 2/3 in. (17mm) in diameter.
When making the purchase, please note that this product was designed as a toy but is being offered for educational use only.