Welcome to the first issue of GeT: The News—the newsletter for GeT: A Pencil! The idea with this newsletter is to deepen our community bonds and share ideas. We plan to publish it three times a year and to include not only news from the GRIP Lab about our GeT Support project, but also essays […]

We are all members of the Euclidean Archetype workgroup. As we summarized in our report, a GeT course organized around the Euclidean archetype will focus on the axiomatic development of fundamental principles of geometry. Informed by the spirit and organization of Euclid’s Elements, this course emphasizes mathematical precision, rigorous proof, and clear communication. We have […]

There are good reasons why the theorems should all be easy and the definitions hard. -Michael Spivak In this article, we look at a selection of tasks related to the angle bisectors of a quadrilateral and discuss their potential function in GeT courses. An instructor may choose to begin an exploration of the properties of […]

The mathematics education literature on student errors has documented how sometimes what students learn can be overgeneralized as they solve other problems and can even occasion errors. I was reminded of this as I puzzled over something I observed some Geometry for Teachers’ students doing as they worked on the problem of constructing a triangle […]