Deeper questions with percents

The good thing about teaching percents is that they connect to the real world, particularly with money. The bad thing is, it can be hard to find really dynamic problems. Too often, you’re just marking prices up or down in imaginary shops, or looking for discounts at imaginary sales. Not a bad thing to be able to do, but not …


Forgot Algebra

Things are crazy busy, and haven’t posted in too long. I’m not going to change that in any serious way at the moment, but when xkcd throws up something this topical, I have a duty to pass it along here.

Math Salons scheduled, plus a great new look at vast amounts of dollars

Happy post-Thanksgiving! To all Seattlites looking for a math-rich event for kids, we’ve finally got some Math Salons on the calendar, starting in January. Interested in joining us? Just rsvp, and we’ll see you there. In other news, Randall Munroe recently created this incredibly dense poster of information, tracking money, how much of it there is, and what it gets …



Katherine and I recently got into a big discussion with our friend Peter, who makes low cost, super-efficient wood stoves for use in the developing world (check out Burn Labs for more). We were trying to convince him that our long term goal of creating a world where mathematical literacy and critical thinking were the norm both in and out …

Addendum to the post: On Danger

I blogged On Danger a little while ago (best viewed in the archive, over here), and this xkcd post is the perfect followup.

This post is an addendum to the last post

Great comments in the last post! In the spirit of self referential comedy, I have to include one of the suggestions mentioned there: If you go to the original comic, you get an extra self referential joke in the rollover.

A timely comic

Link: A timely comic Given my recent talk and blog on the Collatz conjecture, it’s fun to see xkcd mock it here.