## Rate of Change

I often promote the idea that if a concept is important, we should teach it more than once, and preferably in more than one way. Rate of change is one such concept. It can be approached in various ways from middle school to calculus. Is there anything to add to the oft-repeated “rise over run”… Continue reading Rate of Change

## The Calculus Project

This is a guest post by Adrian Mims, one of the author of the open letter I responded to in Yet More on the California Framework (Part 1) and (Part 2). Read it, and click on the links therein.  -- Henri --------------------------------------------------------------------- Hi Henri, Thank you for sharing the links to your posts. The one… Continue reading The Calculus Project

## Asilomar Notes: Story Tables

In my last post, I shared notes from the California Math Council meeting last weekend. I focused on a couple of talks about the use of technology (Asilomar Notes: Tech). Today I write about a different sort of tool, the story table. Shira Helft and Taryn Pritchard’s Asilomar workshop introduced us to this powerful representation of algebraic expressions,… Continue reading Asilomar Notes: Story Tables

## More Calculus, Less Understanding?

Sooner is not necessarily better! If you're a long-time reader of this blog, you may remember my posts about hyper-acceleration. (I have combined those into one article on my Web site.)Today, a guest post on acceleration by Robin Pemantle, a mathematician at Penn, who addresses this topic from his point of view as a university… Continue reading More Calculus, Less Understanding?

## Doctor Dimension Returns!

In a post a few weeks ago, I told the story of Doctor Dimension, the two-dimensional scientist who spends his fictional life filling two-dimensional containers with two-dimensional liquids, and has been doing this since 1994. In the comments, two different Bay Area math teachers directed me to Water Line, a wonderful Dan Meyer /  Desmos… Continue reading Doctor Dimension Returns!

## World Cup Fever

The World Cup happens mostly during summer vacation, which is unfortunate, because it provides a great context for a geometry exploration.I start my book Geometry Labs with lessons about angles, starting from the very basics, and moving on to the inscribed angle theorem. (The book is available in its entirety as a free download here.… Continue reading World Cup Fever

## Doctor Dimension

Twenty-some years ago, I started teaching an advanced high school geometry elective class called Space. I offered it every other year until I retired last year. Most of the course was about transformational geometry and symmetry. (That turned out to be excellent preparation for Common Core geometry. I will be presenting and co-presenting four workshops… Continue reading Doctor Dimension

## the function dance!

A friend on Google+ posted this image:<a href="data:<img alt="" border="0" src="data:I have often performed "the cubic dance" (see above!) for my students. I've also often asked them to "air graph" various functions.One complication is the fact that left and right are reversed for the person watching you, and while I try to perform things "backwards"… Continue reading the function dance!

## Asilomar Report, Part 2

Read about my morning at the Asilomar meeting of the California Math Council here.My afternoon was taken up with function diagrams. First, I attended Martin Flashman's presentation on this topic, then I made my own presentation, and finally I had dinner with Martin. (If you know nothing about function diagrams, read no further. Or find… Continue reading Asilomar Report, Part 2

## Function Diagram Slides

I posted slides from last Saturday's talk about function diagrams on my Web site. I don't imagine they'll be that useful, unless you want to use them in one of your presentations, but on the same page you can read the article the presentation was largely based on, and find links to many PDFs, animations,… Continue reading Function Diagram Slides