One topic that has nearly vanished from my teaching is the solving of inequalities "by hand". There are several reasons for that choice:The techniques are difficult to teach and difficult to learn, because they are so close to the ones for the solving of linear equations, but differ in one crucial case.It is difficult to… Continue reading Solving Inequalities
Tag: Algebra
The third dimension!
This is another post about sessions I attended last weekend at the Asilomar Northern California CMC conference. (To read the whole set, start here.)Kevin Rees presented two variations on a classic volume optimization problem. In the traditional problem, you start with a square piece of cardboard, cut off congruent squares at the four corners, and… Continue reading The third dimension!
Workshops in New York in August
I will be leading two summer workshops for teachers in New York City, Aug 13-17.The early-bird registration discount (15% off) is being extended to June 25.VISUAL ALGEBRAI have offered this 3-day workshop, and various parts of it, many, many times. It's about intelligent use of manipulatives and technology, plus a parallel axes representation. Also: three… Continue reading Workshops in New York in August
Puzzles in math education
Scott Kim, the author of the excellent Inversions, is launching a crusade to bring more puzzles to math education. He gave a talk on this subject at the Gathering 4 Gardner. (See the slides.) Martin Gardner, of course, is the author of the long-running Mathematical Games column in Scientific American. He inspired who knows how… Continue reading Puzzles in math education
Presentation at SF State, May 1
I was invited by the San Francisco Teachers' Math Circle to present some problems. Here's the basic info.When: Tuesday, May 1 at 6:00 PM Where: Trailer P (behind Thorton Hall) at San Francisco State University 3699 19th Avenue, San Francisco, CAAs far as I know, the event is free, and dinner is included!I will present a pattern… Continue reading Presentation at SF State, May 1
Early Bird Discount
About three months ago, I mentioned my summer workshops for teachers and summarized how they will differ from their previous incarnations.Brief recap:- Hands-On Geometry, June 18-21 in San Francisco- Visual Algebra, August 13-15 in New York City- Re-imagining High School Math, August 16-17 in New York CityThe workshops are sponsored by the Center for Innovative… Continue reading Early Bird Discount
The Quadratic Formula
In the period following the publication of Algebra: Themes, Tools, Concepts, we started asking our Math 1 students to write and illustrate a short report or poster, tying in four representations of a trinomial in the form x^2+bx+c. (Math 1 is Urban School's Math Department's version of Algebra 1, sort of.) I just posted a… Continue reading The Quadratic Formula
Additional notes on ATTC
I just added one final page about Algebra: Themes, Tools, Concepts. It consists of errata and other notes I took in the first few years after the book was published, in anticipation of a second printing or second edition that never happened. It may be a useful complement to the abundant notes in the Teachers'… Continue reading Additional notes on ATTC
ATTC upgrade
Algebra: Themes, Tools, Concepts (ATTC) is an algebra textbook I co-authored with Anita Wah in the early 90's. It was ground-breaking in some ways, and includes many extraordinarily effective approaches to the teaching of algebra. In fact, ATTC features powerful lessons on many parts of secondary school math, which are used by teachers in grades… Continue reading ATTC upgrade
Escape! Meeting notes 3 — habits of mind
This is the third and final installment of my notes from the Bay Area fall meeting of Escape from the Textbook!(Part 1) (Part 2)We ended the meeting with a segment led by Avery Pickford. (See his notes about the meeting.)He presented this problem:(He didn't present it exactly like this -- this is how the problem… Continue reading Escape! Meeting notes 3 — habits of mind
Henri's Math Education Blog 