Convex Tangram Polygons

If you’re a regular reader of this blog, or visitor to my website, you probably know of my long-standing interest in geometric puzzles. Among those, tangrams are probably the most well-known and widely available. Thus I included them in Geometry Labs (free download) where they are the subject of Section 2, and Lab 10.6. In this… Continue reading Convex Tangram Polygons


In 2006, I attended the Park City Mathematics Institute. I shared some of the work I did there on my website. Here is some information about this summer’s program, from the amazing Peg Cagle. -- Henri —————————————————————————————————— An immersive, three-week residential program, the Park City Mathematics Institute / Teacher Leadership Program provides participating secondary math… Continue reading PCMI

For Algebra

The Atlantic published an excerpt from Temple Grandin’s latest book (Visual Thinking). They titled it “Against Algebra”, which puts it in a tradition of anti-algebra pieces in various magazines and radio programs (!). Alas, anti-algebra ideas are also present among some math educators. I have written about this repeatedly: Technology in Math Education (2022) My… Continue reading For Algebra