Thursday, September 2, 2010

Oh dear...

Emily amused by one of those trendy American productivity gurus
Beloved Emily reminds me that I only have the pleasure of her company until Sunday, when she heads back off to start teacher training. So it's OK for me to neglect my blog and show her the proof of Heron's Theorem. This is a very fine piece of Hairy Algebra which delivers the Happy Ending just at the very last minute. It's like a Rubik's Cube or a P G Wodehouse story: where you are hopelessly lost in an impenetrable plot problem until you turn the last couple of pages / make the final couple of twists and suddenly all is well.

Sometimes life's like that.

I don't remember seeing this at school: I got the proof from khanacademy. And I don't remember hearing about khanacademy itself before seeing a tweet from Steve Clayton (wonderful stuff, but not much of a disguise) a few days ago. The entire US Maths school syllabus (and much more) delivered in ten minute YouTube videos. All done by one man with the aid of an electronic blackboard. How does he maintain his work rate?

I only need one excuse a day, of course, to maintain my current level of production indefinitely.