Abstract: There is provided a design and construction toy having a plurality of relatively rigid elements, wherein each element has: a first side member and a second side member, with each of the side members having an outer face, an inner face, a top face and a bottom face, and the first side member and second side member are joined at ends thereof to form an apex and to provide a formed equilateral triangle with an open base; a predetermined distance between the outer face and the inner face, whereby a derived distance is established between the inner face and the outer face along the juncture of the joined ends at the apex; a lateral distance between the top face and the bottom face which is at least 0.1 and no more than 5.