The Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010) propose a new vision for the mathematics classroom with updated content standards and Standards for Mathematical Practice (SMP). These practices are founded on NCTM processes (Problem Solving, Reasoning and Proof, Communication, Representation, and Connections) and abilities…

Twenty years ago when the author was student teaching, he quickly learned what geometry teachers and researchers (e.g., Senk 1985) have long known: High school geometry students struggle with proof. Throughout his career, he has tried to create instructional materials to make proof more accessible to his students. From field-testing materials with…

Presents a model for teaching reasoning using technology in the contexts of algebra and geometry. (MKR)

The problem of finding all topological spaces is considered. Two characterizations are presented whose proofs involve only elementary notions and techniques. The problem is appropriate for students in a beginning topology course after they have been presented with the Embedding Lemma. (DC)

Describes several short geometry tasks that go beyond the simple recognition of figures and properties. Presents scoring rubrics and questions that might be useful to middle school teachers developing short open-ended questions that encourage and assess students' thinking. (ASK)

Described is how using LOGO tools for manipulating embodiments of geometric objects helps students construct more abstract and coherent concepts. Discussions are included on developing verbal definitions versus constructing concepts, tasks for integrating turns and angles, group discussions, and maze tasks. (KR)

Discusses a variation on tiling that offers opportunities for the construction of the fundamental mathematical concept of constructing abstract units called "unitizing." Tiling integrates geometric and numerical settings to develop spatial sense and present mathematics as constructing patterns. (MDH)

Students with or without disabilities often experience difficulties with abstract math concepts. This paper is intended to help solve the mystery of math concepts through origami construction, a hands-on activity. Students are involved in constructing and deconstructing concepts by folding and unfolding a piece of paper which eventually leads to a…

Describes the Plane Geometry System computer software developed at the Educational Computer Systems laboratory in Sofia, Bulgaria. The system enables students to use the concept of "algorithm" to correspond to the process of "deductive proof" in the development of plane geometry. Provides an example of the software's capability…

Presents a series of four worksheets to develop students' perception of spatial relationships. The tasks require students to use cubes to build models and describe the models by representing the front, right, and top views on grid paper. Provides reproducible worksheets. (MDH)

Presents a discussion illustrating student reasoning while using LOGO to draw tilted squares and rectangles. Suggests that teachers recognize that many students use visual imagery to reason and discuss visual reasoning with students. Gives examples of tasks to promote discussion. (MDH)

The 1989 document, "Curriculum and Evaluation Standards for School Mathematics" (the "Standards"), provides a vision and a framework for revising and strengthening the K-12 mathematics curriculum in North American schools and for evaluating both the mathematics curriculum and students' progress. This book, one in a series…