What I Tell Myself After a Bad Lesson

I've had lots of chances to give myself this pep talk. Lots.

Why “Competitive Marketplaces” are an Awkward Fit for Education

Nothing against markets. A little something against educational ones.

UK vs. US: Who’s got the right way to teach math(s)?

Sure, we love to hate on our own system. Just don't tell us yours is better.

“Explanation is work for second-rate minds,” said the monster.

You want to make my blood boil? Just quote G.H. Hardy.

Decimal-Crazed Lunatics

My students have lost their grip on mathematical reality.

An Open Letter to Benedict Carey

A dispatch from the trenches of the "math wars."

US vs. UK: Who Grades Students?

The word "grade" belongs on that List of Words That Change Meaning Dramatically When You Cross the Pond.

The Master, the Pupil, and the Clumsy Game of Chess

In my recommendation letter for his college apps, I described Zhi as “a superhuman student sent to our school from the future.” I stand by it. His diligence is otherworldly.

Tic-Tac-Toe Puzzles (and the Difference Between a Puzzle and a Game)

I’m still stunned by the response to my post on Ultimate Tic-Tac-Toe, which spawned a whole fleet of mobile apps, was translated into Spanish by the Argentine Department of Education, and has drawn more than half a million visitors.