Abstract: A manipulative three-dimensional puzzle including a shell member formed with a plurality of tracks including a first set of tracks and a second set of tracks, the first and second sets of tracks intersecting each other at a plurality of crossroads, the first and second sets of tracks together extending at least partially over a height, length and width of the shell member, and a plurality of puzzle pieces and a plurality of spacers movably positioned in the first and second sets of tracks, wherein for each track at least one spacer is between two puzzle pieces, and wherein moving one of the puzzle pieces in one of the tracks causes all the puzzle pieces and spacers in that track to move together along that track.