By George Hart for the Museum of Mathematics


By pleating a square sheet of paper with a pattern of concentric squares, one can fold a saddle shape that mathematicians call a hyperbolic paraboloid, sometimes nicknamed a hypar. Erik Demaine led a workshop at a recent Museum of Mathematics event where he showed how multiple hypars can be assembled to make star-like geometric forms. During the Math Encounters presentation, fifty people folded hypars and joined them to make this construction.

There are twenty four sheets all together, arranged as a group of four for each face of an imagined cube. Erik’s paper about the mathematical ideas and detailed folding instructions to make your own pleated hypars are available on his web site, here.

See all of George Hart’s Math Monday columns

Gareth Branwyn

Gareth Branwyn

Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy person’s memoir,” called Borg Like Me.

  • basyfeltn

    My seven year old grandson is very good at math and science and wishes he could make something like this.  is there any place on the web for simpler math based crafts that he could make?
    email me at basyfeltn AT verizon DOT net if you can help with this… thanks, Kitty