The face puzzle, a box of wooden jigsaw pieces, looks like a child’s game, a primitive, flattened-out version of Mr. Potato Head. Start with the biggest piece, a half-inch-thick hunk of wood ...

Not only do his varied puzzle box designs show his math background, but they are all made entirely of wood. There are no nails or fasteners; just intricately-fitted wood and some glue. There’s a ...