Way back in the early 90's, I co-authored the textbook Algebra: Themes, Tools, Concepts (ATTC) with Anita Wah. It failed to become a best-seller, in part because while the lessons work well with students, the book is not very easy for teachers to manage. Still it's a good book. We have continued to use different… Continue reading Algebra: Themes, Tools, Concepts and the Common Core
Author: hpicciotto
Summer Workshops
I'll be teaching four workshops in June, at the Urban School of San Francisco's Center for Innovative Teaching. I just posted the info here. Some changes from past years:I've broken up my Geometry workshop, which used to be three or four days, into two chunks, two days each. The first (Hands-On Geometry) will be based… Continue reading Summer Workshops
Asilomar report, Part 1
Once again, I had a great time at the Asilomar conference of the California Math Council. Here are some notes from the first two sessions I attended.Scott Farrand (of Cal State Sacramento) and UC Davis's Rick West's presentation "Diophantine Equations Can Hide Geometric Surprises" was a fun way to start the day.Think of two whole… Continue reading Asilomar report, Part 1
No Three on a Line
In a recent post, I mentioned K-12 Unsolved, the project I'm involved in that aims to publicize 13 unsolved math problems, in the hope that an appropriate version of each problem will find its way into K-12 classrooms. One problem we looked at was posed by Henry Dudeney in 1917. Here is the problem: Consider… Continue reading No Three on a Line
Geoboards and Dot Paper
If you are familiar with my curricular creations, you know that I often use the geoboard as a microworld to introduce interesting problems and important concepts. This is in line with my call for a tool-rich pedagogy. (A geoboard is a square lattice pegboard on which students use rubber bands to create and investigate geometric… Continue reading Geoboards and Dot Paper
HTML 5!
In preparation for my Asilomar talk, I have updated all my function diagram Java applets to HTML 5.What that means is that (a) you won't get the annoying and scary message warning you of the dangers of Java, (b) the applets will work on a tablet, and (c) you won't need to have GeoGebra installed… Continue reading HTML 5!
"Enrichment"
During my first ten years as a teacher, I worked in elementary schools. In addition to team teaching my own class (grade 3, then 4, then 5) I was a math specialist for grades K-5. The basic idea was that there was "normal" math (a lot of arithmetic, textbook-based), and there was "enrichment" math. I… Continue reading "Enrichment"
Function Diagrams update
Presentations at AsilomarI will be speaking about function diagrams at the December 7 meeting of the California Math Council (North) in Asilomar. I hope to see some of you there!I first learned about function diagrams at Asilomar, many years ago, from Martin Flashman, a professor at Humboldt State University. Strange coincidence: Martin is also going… Continue reading Function Diagrams update
Unexpected ratio
Triangle ABC is equilateral. MA/ME is the golden ratio! (George Hart showed me this result some time ago.)Vynce Montgomery pointed out that therefore, this could be a way to construct a pentagram. To respond to this challenge, I hid everything but MA and ME, and proceeded from there:--HenriPS: thinking about this a few days later,… Continue reading Unexpected ratio
Crowd-Sourcing
Well, not much of a crowd, because not many people read this blog. Still... I created four worksheets of sorts, each one consisting of a short title and images of a dozen circles. Each circle is divided pizza-like into slices, as in the example above. The four titles: Angles, Fractions, Time, and Percents/Money. Here is… Continue reading Crowd-Sourcing
Henri's Math Education Blog 