Raymond Smullyan

The logician and puzzle-maker Raymond Smullyan died yesterday at the age of 97. After reports circulating on twitter, the news was confirmed, and articles in memorium have begun to appear. Smullyan was a brilliant designer of puzzles, and his books, especially The Riddle of Scheherezade, had a big impact on me. His idea of coercive logic, in particular, impressed me …

An Interview with Emily Grosvenor, author of Tessalation!

Tessalation! is a new children’s book about a little girl who discovers tessellations in the outdoor world. I backed the project when it was on Kickstarter earlier this year, and my book just arrived. Both the drawings and the writing is beautiful, and it is, to my knowledge, the only book for kids about tessellations. Emily Grosvenor, the author of …


Quick Physical Games for the Math Classroom

We hold these truths to be self-evident, that kids need to move around, and creating opportunities to move during math class can pay off in spades. Therefore, we have a collection of some of our favorite math/movement quick activities to share. These are especially good for K-4, though they’re adaptable to older and younger grades too. They provide a dose …


Three Square Problem and Variations

I just saw an absolutely charming problem on Numberphile that I was shocked never to have seen before. They call it the Three Square Problem (featuring Professor Zvezdelina Stankova).  Three Square Problem Prove that It feels, as Prof. S says in the video, like a beautiful conjecture. I highly recommend trying to come up with a proof. There are many (54!), and …

Found note: “List of Counterexamples”

I found this note when I was cleaning out some old papers. It’s like finding a strange little gift from the us of the past. List of Counterexamples Communism Hitler Klein 4 group Petersen graph Plasma Hawaii Neutrinos Tacoma Narrows bridge Rwanda The 1% Duck-billed platypus Seahorses


Making sense of math

Math makes sense. Not only to mathematicians, it turns out. Math just makes sense. It’s internally coherent, and shows you so when probed. All the rules in math that seem like “just because”–you can think of them probably pretty quickly, like don’t ever divide by zero, or a number raised to the zeroth power equals one, or to divide fractions …


Math For Love meets Washington STEM

We are happy to announce that we’ve received an investment from Washington STEM to expand our work with teachers in Seattle area schools this coming year! We’ll be running math circles for teachers from schools that serve underserved and underrepresented kids, working to spread the love far and wide. We are still in the early stages of arranging the project, …


When Girls Leave Math and What To Do About It

The conversation around gender and mathematics is often driven by poignant anecdote or by statistics. We have either the individual story of heartache or we have a set of disheartening numbers, and in either case, I feel frustrated. But every now and then a study comes out that gives more specific data, data which gives one a sense of honing …


What math curriculum actually works?

Reading the opinions and rants of various math curricula, I see how hard it can be to evaluate the strengths and weaknesses of a given math textbook. Is Saxon better than Everyday Math? What’s the best intervention for pre-K? When someone tells me that my school’s math book is “bad,” should I believe them? A place to look for real …

Next Math Salon: January 24. Plus T Shirts!

The next math salon is January 24 from 4pm-6pm at Mosaic Coffeehouse, in Wallingford, Seattle. The event is free, though donations are welcomed. Please rsvp if you’d like to be there. Also, Math for Love T shirts have arrived! Right now it’s just children sizes, but men and women’s tees should show up soon.