When are crowds smarter than individuals? And could it possibly happen in, of all places, Twitter?

A big-name new book, featuring a few of my scraggly illustrations.

Your chance to help shape a forthcoming book.

A 9-year-old scrawls an innocent problem... and suddenly 3D surfaces are intersecting in 4D space.

Tricky equivalences.

Four teams. Four probabilities. This shouldn't be that hard... right?

A pencil-and-paper game for the snake-fearing (or snake-loving) mathematician.

How many clicks will this post get?