The Truly Common Core

Math education is succeeding beautifully... for the right definition of "success."

Felt-Tip Geometry

Four beautiful new puzzles.

And 20 more of my proudest math cartoons.

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

Catriona Shearer strikes again.

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

Thirty favorites (not including the one I wrote).

How many clicks will this post get?

The February 29th page is a flowchart for whether you need the February 29th page.

I mean, other than the fact that we're old.