Abstract: A construction apparatus has a plurality of relatively flat components (8,50,56,88,90) having at least three sides, an elongated rod-like member (25,52) extending along each side and enlarged corner portions (26,54) between the members. A plurality of connectors (6) is provided for connecting together adjacent sides of adjacent members to form structures. Each connector has a pair of recesses (62,64) shaped to releasably embrace adjacent pairs of members (25,52). The recesses of each connector open outwardly in a common direction so connectors may be positioned on pairs of members without altering previously formed portions of the structure.