If you don't know what a flexagon is, take a peek at Hart's YouTube video about this geometric marvel. Even if you DO know what a flexagon is, the Vi Hart video is really, really cool! There's no better way to kick off Flexagon Month!
Basically, a flexagon is made from a folded strip of paper; it can be flexed so that it has more than the original two sides. It's a bit like a mobius strip (only completely not).
Flexagon.Net has clearly labeled templates for making flexagons, tips for folding, and other ideas to further your exploration.
You should definitely check out Hart's other entertaining math videos. I love her doodles and dots! Actually, I love her everything!
Maybe October should be Vi Hart month!
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