Tarquin Group 2020 2nd Edition 96 pages

The first edition of Mathematical Origami was published in 1997 and had 64 pages. This second edition has 144. Only six of the designs in the first edition are included in the second, so you need to invest in both editions! Both editions are primarily aimed at mathematics teachers, but it will certainly appeal to recreational mathematicians and modular origami enthusiasts. The book explains how to fold and assemble simple units from ordinary photocopy paper, mostly without glue, into polyhedra which are strong enough to stand up to handling in a classroom environment.

The author lists the advantages of making polyhedra in this way:

• The process of creating the shapes and of folding the modules is itself highly mathematical in nature.
• Modules / polyhedra can be made as group projects.
• All polyhedra built from the same type of module can be used as combination puzzles and to investigate “space filling”.
• Finished polyhedra can be taken apart and the modules re-used to build other polyhedra.
• Modules of different colours can be swapped to create different surface colourings of the same shape.
• Damaged modules can easily be replaced!

The book is divided into three main sections: Equilateral Deltahedra, Rhombic and Semi-Rhombic Polyhedra and Planar Polyhedra. The modules are folded from a range of rectangles of differing proportions, squares, silver rectangles, bronze rectangles and golden rectangles. Using a range of rectangles makes folding the modules much easier than is sometimes the case with other systems of modular polyhedral design. The book also shows you how to fold templates to make it easy to construct rectangles of the correct proportions in the quantities required.

As always, Mitchell’s diagrams and text are clear and helpful, you should have no problems following them and thankfully(!) you don’t need more than a few sheets to make most of the designs. As well as the folding, you’ll learn a lot of useful maths. For some unknown reason the cover includes a picture of a modular paper sculpture that isn’t in the book – don’t blame the author (my eternal cri de cœur)!

The second edition of Mathematical Origami can be purchased in hardcover, paperback or various ebook formats from: https://www.tarquingroup.com/mathematical-origami-second-edition.html.