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Time and Place

Wednesday-Friday, June 28-30
9:00 a.m. to 3:30 p.m.
at the Head-Royce School in Oakland, CA


The Common Core State Standards call for a complete rethinking of geometry in grades 8-11. Instead of basing everything on congruence and similarity postulates, as is traditional, the idea is to build on a foundation of geometric transformations: translation, rotation, reflection, and dilation.

In order to teach this effectively, it is important to have a solid understanding of the underlying math, as well as ideas for rich activities for students. I have been teaching transformational geometry for twenty years, and have a lot to share. This three-day workshop will cover:

  • The implications for the teaching of proof.
  • Composition of transformations -- the four isometries and their fundamental properties.
  • Symmetry in depth -- around a point, along a strip, in the plane. Connections to art and design.
  • Computing geometric transformations with the help of complex numbers at first, then matrices -- this is the mathematics that underlies all computer graphics.
  • Transforming graphs: all parabolas are similar
  • Intelligent use of technology to support all this, including a highly motivating unit on geometric construction.

Guest presenter: Lew Douglas

This workshop does not overlap with Hands-On Geometry.


I am happy to offer a workshop on transformational geometry to your school or district. Contact me.