Mathematical paper-folding blows our minds

"Mathemusician" Vi Hart explained the boggling properties of the folded-paper hexagon.

In school, one thing you could do at your desk when you were bored was fold things out of paper torn from your folder or exercise book — chatterboxes, for playing games that usually had something to do with boy/girl germs; cubes, because they look rad; paper aeroplanes, because yours were the best.

Hart, who works for the Khan Academy, paper-folds all that under the table with her "Hexaflexagons". It's a strip of paper folded into a neat hexagon, and somehow has more sides than it does (if you're confused by this statement, the video will reveal all). It looks more like sorcery than maths. We actually think Hart should change her appellation to "Mathemagician".

She didn't invent the shape herself, though — that honour belongs to one Arthur H Stone, as Hart explains on her YouTube page, and which you should visit and subscribe to.

Check it out and be amazed: