Just a plug for a great fun competition where students compete against students from schools around the world.
The competition starts for real next Tue or Wed depending which timezone you are in and runs for 48 hours. Officially WMD is 3rd March.
At the moment schools and individuals can register and do practice rounds against other people.
All the info is on www.worldmathsday.com.
It is addictive; my two teenagers are hooked and love seeing where their opponents live. There is a free iPhone app too. They will be doing the competition in their maths classes in school next Wednesday.
Over one million students round the world have already registered and at this moment over 6000 are playing online. I can't think of a more popular maths event. And it is completely free.
They get to dress their own avatar too.