Dammit - if they'd been teaching me A level maths, instead of the two teachers who just left us to get on with a book, I'm sure I'd have passed it.

I recognise a matrix on the back of the first girl on the left, and the integration/differentiation, but not what's on the other girls...

Oh yeah, and I agree they are hot - I assume they are geek girls, and not just the writer, and I'd love to get intellectual with them (and perhaps something else beginning with 'i')...