This past weekend, Anthony & I celebrated Martin Gardner's birthday with a weekend of hexaflexagon building, learning, and flexing! If you unfamiliar with flexagons, I highly recommend watching ViHart's videos: This One, This One, and This One.
We managed to build several hexahezaflexagons on Saturday with a dodecahexaflexagon to cap the night (yes - that is a 12-faced hexaflexagon)! On Sunday, we continued the fun by attempting some of the more unusual hexaflexagons. Anthony worked on tetrahexaflexagons as well as pentahexaflexagons (Hexaflexagons with sides that are not a multiple of 3 are far more complicated). After several failed attempts, I managed to build a working 48-sided hexaflexagon. Of course, it is a bit thick & delicate... but fun.