Tired Of Iron Filings?

Same here. Try the Ferrofluid Magnetic Display, a little sealed bottle with virtually fluid nano-particles of ferrous metal suspended in liquid. You’ll get (4) powerful 1/2” dia x 3/16” neodymium disc magnets, (2) of them attached to chess-pawnish holders. Move the magnets in assorted combinations around the bottle for fascinating effects. Sort of the marriage of science with desk toys, but students can’t spill these particles all over the place.