[al_biglan]

This is a great way to teach math. Model something that is interesting but only needs to rely on some basic principles (geometry, series and limits in this case). Best quote of the piece: "Britney found it interesting to realise that when we fold a piece of paper, we are actually finding a solution to a quadratic equation!"

[Rangi42]

You can even solve cubic equations with origami[1], which is what allows you to double a cube and trisect an angle by adding folding to the usual tools of compass and straightedge. (It's still not enough to square the circle.)

[1]: http://math.stackexchange.com/questions/581958/solving-cubic...