Cardboard has always been associated with the box the toy comes in—to a small child it’s often as much fun as the toy itself. Toymakers like Calafant and Kids on Roof have discovered just how versatile (and fun) cardboard can be, and have started making the toys themselves out of the recyclable material. Far from being one-dimensional, cardboard can be folded and tucked to create a world of possibilities, from dollhouses and toy cars to brilliantly detailed airplanes.