Many students have weak arithmetic skills. Many teachers blame this on calculator use, but it is just as likely that the real reason lies elsewhere. For one thing, the teaching of arithmetic traditionally does not involve developing any understanding, so the learning is shallow and fragile. For another, students correctly feel that mindless arithmetic is… Continue reading Calculation

Time and Tide

This is my yearly report on the Asilomar conference of the California Math Council, Northern Section. Because I was presenting three times, I didn't end up attending as many sessions as I would have liked. As always at Asilomar, I enjoyed hanging out with my ex-colleagues, running into friends, and meeting the occasional fan of… Continue reading Time and Tide


In between June 27 and August 4, 2016, I presented seven to ten workshops (depending on how you count) ranging from a couple of hours to four days. I share most of the handouts, resources, and slides on my Summer Workshops site. (See below my signature for more details on what's there.)The site will remain… Continue reading Eclectic

Making a Vector in Desmos

A couple of years ago, during a workshop on transformational geometry, a participant objected when I used and recommended GeoGebra and not Desmos. Her main argument was that students love Desmos. Fair enough, but that does not make up for the fact that Desmos is about graphing, while GeoGebra includes the many basic and not-so-basic… Continue reading Making a Vector in Desmos

Pattern Blocks on Pi Day

I'll be offering a workshop for middle school and high school teachers on March 14 at the American Institute for Mathematics in San Jose. My topic is pattern blocks:<img alt="" height="76" src="data: Pattern blocks are ubiquitous in elementary schools, but they're not commonly seen in middle school or high school. Yet, they do offer plenty of… Continue reading Pattern Blocks on Pi Day

Interactive Whiteboards

Some years ago, I wrote about interactive whiteboards (IWBs), in response to a passionate anti-IWB opinion piece I stumbled upon. The author of that piece objected to IWBs on multiple grounds, some of them legitimate. But I disagreed with his main point, which was to counterpose IWBs to student-centered pedagogy. To me, those are not… Continue reading Interactive Whiteboards