FEATURES 
Is There a “Best” Rectangle? R. Alan Russell In trying to find the ideal dimensions of rectangular paper for folding origami, students explore various paper sizes, encountering basic number theory, geometry, and algebra along the way. 
Sketching Up the Digital Duck Kathryn G. Shafer, Gina Severt, and Zachary A. Olson Two preservice teachers describe how using Google SketchUp, Terrapin Logo, and The Geometer’s Sketchpad fosters a deeper understanding of measurement concepts. 
Teaching the Perpendicular Bisector: A Kinesthetic Approach Ayana Touval Through movement—a welcome change of pace—students explore the properties of the perpendicular bisector. 
The Shape of an Ellipse Gregory D. Foley Ellipses vary in shape from circular to nearly parabolic. An ellipse’s eccentricity indicates the location of its foci, but its aspect ratio is a direct measure of its shape. 
More on Ellipses and Polar Coordinates

Navigating between the Dimensions Julian F. Fleron and Volker Ecke Two classroom activities—the Flatland game and sliceforms—are useful vehicles for student exploration of the geometric interplay between the dimensions. 
Stop Teaching and Let Students Learn Geometry Michael J. Bossé and Kwaku AduGyamfi A geometry course for teachers—easily adaptable to a high school geometry class—integrates technology, reasoning, communication, collaboration, reading, writing, and multiple representations. 
Instructions for the EGASP Examples of the EGASP

Second Look: Geometry

Recreating History with Archimedes and Pi Lora C. Santucci Students use modern technology to investigate historical perspectives and calculate an approximation of pi. 
Thinking Deeply about Area and Perimeter Wayne Nirode Using a 6inchsquare sheet of paper and a simple rule for creating a polygon, students can explore interesting area and perimeter problems. 