Of course I know how magnets work (ok, I kind of know how magnets work), but somehow they still seem a little bit like magic: these wonderful surfaces that things mysteriously stick to, seemingly in defiance of the law of gravity
DIY Sand and Rock Box by FSPDT. Gdjk -> made this with toilet rolls (aka tunnels) and moon sand instead of play sand. My son loved playing with it. The moon sand cleans up nicely indoors but play sand will be easier to play with when using the small cars.