This is really great! These so-called kaleidocycles are adaptations of Escher's two-dimensional images of fish, angels, flowers, people, etc., transformed into uniform, interlocking, three-dimensional objects whose patters wrap endlessly. The 48 page book contains diagrams, assembly instructions, and a fascinating discussion of the geometric principles and artistic challenges underlying Escher's designs and their transformation to three-dimensional models. The accompany folder contains 17 die-cut, scored, 3-dimensional models that you can assemble. They are in full-color on lightweight glossy card. Fascinating study of art and geometry!