Includes lesson plans and worksheets that deal with transformational geometry, specifically reflections. The lesson for grades three to four focuses on angles of incidence and reflection and that for grades five to six involves mirror images. (MKR)

Presents an inexpensive laboratory experiment that combines the recommended techniques for teaching fractal geometry in the classroom with the standard procedures for studying electrochemical deposition of ramified patterns in the regime of low solution concentration and low applied constant driving force. Introduces students to fractal growth…

Presents a perspective on the nature of the use of proofs in high school geometry. Compares three currently used approaches to the geometry curriculum: (1) traditional geometry with no explanation of the axiomatic system; (2) hands-on geometry with no proofs until the end of the course; and (3) experimental geometry with no proofs. (DDR)

Provides suggestions for implementing the geometry standards in an elementary curriculum by including all aspects of geometry. (KHR)

Analyzes one student's thinking using the Van Hiele levels of geometric thinking. (KHR)

Describes lessons with year 7 and year 9 classes that used the ATM Active Geometry package. Presents the main activities and how to use prepared files in the geometry package for mathematics instruction. (KHR)

Discusses the compass and the straightedge in terms of Euclidean geometry. Includes a worksheet in the text. (KHR)

Provides an historical account of how proving evolved in school geometry. Explains how the two-column proof format brought stability to the course of studies in geometry. Uncovers what the nature of school geometry came to be as a result of the emphasis on student learning. Draws connections between that century-old reform and current reform…

Analyzes different solution strategies to find the area of an octagon. Describes four different generalizations of the original problem and illustrates solutions. (KHR)

Describes using children's and adults' natural curiosity when it comes to bubbles as a perfect vehicle for investigating geometry, data analysis, and measurement. (KHR)

Uses the book "Spaghetti and Meatballs for All! A Mathematical Story" to help children differentiate between the mathematical concepts of perimeter and area. (KHR)

Presents a measurement problem that can be explored by students of varying ability. Discusses aspects that make it accessible in a heterogeneous class. (YDS)

Explains the basics of spherical geometry and describes a series of activities developed for grade 6 middle school students. (YDS)

Describes using clusters of high-quality literature to support the teaching of key geometry and measurement ideas. (Contains 29 references.) (YDS)

Shows how students explored geometric properties of the South Korean flag using proportional reasoning. (YDS)