By George Hart for the Museum of Mathematics


If you knit, here’s a stuffed, dodecahedral thing—I don’t know quite what to call it—a toy, a pillow, a mathematical model? The shape is based on twelve 5-sided units like a dodecahedron. But they bump out, so the form is more like a small stellated dodecahedron. This was designed by Norah Gaughan, who provides instructions in this Berroco pattern.

If you prefer to crochet, here’s another variation by Betsy Myles, also for Berroco.


See all of George Hart’s Math Monday columns

Becky Stern

Becky Stern

Becky Stern ( is a DIY guru and director of wearable electronics at Adafruit. She publishes a new project video every week and hosts a live show on YouTube. Formerly Becky was Senior Video Producer for MAKE. Becky lives in Brooklyn, NY and belongs to art groups Free Art & Technology (“release early, often, and with rap music”) and Madagascar Institute (“fear is never boring”).

  • Marcello Cardoso

    that, to me, is a katamari 

  • Emily Shreve

    I’d like to mess with the patterns to knit flat sections for a big plush D20.