Generalizing, conjecturing, representing, justifying, and refuting are integral parts of algebraic thinking and mathematical thinking in general (Lannin et al., 2011). The activity described in this article makes a case for generalizing as an overall mindset for any introductory algebra or geometry class by illustrating how generalization problems…

Continuing our critique of the classical derivation of the formula for the area of a disk, we focus on the limiting processes in geometry. Evidence suggests that intuitive approaches in arguing about infinity, when geometric configurations are involved, are inadequate, and could easily lead to erroneous conclusions. We expose weaknesses and…

The present study investigated (a) whether the perceived cognitive load was different when geometry problems with various levels of configuration comprehension were solved and (b) whether eye movements in comprehending geometry problems showed sources of cognitive loads. In the first investigation, three characteristics of geometry configurations…

Initial exposure to algebraic thinking involves the critical leap from working with numbers to thinking with variables. The transition to thinking mathematically using variables has many layers, and for all students an abstraction that is clear in one setting may be opaque in another. Geometric counting and the resulting algebraic patterns provide…

The author explores relationships among the lengths of sides of a triangle, one of whose angles measures 60 degrees. A computer program designed to search for special triangles is included. (SD)

Uses colored cube combinations to investigate surface area, volume, and axes of symmetry. (ASK)

Argues that mathematics is, to a large extent, the study of patterns. Presents an activity in which students search for patterns in the Fibonacci sequence and Pascal's Triangle. (ASK)

Describes an activity that utilizes four pattern blocks to help students understand and explain perimeter. Engages students in making and supporting conjectures about a scenario that involves trains composed of various shapes with different perimeters. (DDR)

Five activities involving an array of numbers called an even triangle are given. Properties of the triangle are listed and some generalizations are proven. (MP)

Properties of the harmonic number triangle are listed, and ways of generating the elements of harmonic triangles are described. (MNS)

Presents three sets of polygons marked so that visually appealing designs emerge when the polygons are assembled into tessellations that cover the plane. Provides ideas for using the different sets of tiles in the classroom and reactions of the students who assembled the patterns. (AIM)

Provided are student activities to introduce the geometric concepts of line symmetry and rotational symmetry as related to Hawaiian quilting patterns. Paper squares, scissors, and folding techniques afford the teacher the chance to stimulate class discussion about pattern recognition and to integrate mathematics with the cultural world outside the…

Presented is an activity that explores the relationship between the size of a rectangle and the number of squares intersected by a diagonal. Students incorporate pattern recognition and the concept of the greatest common divisor in solving the problem. A sample worksheet is provided. (MDH)

The goal of this book is to help students make sense of mathematics and become confident in their ability to do so. Section 1: "Foundations of Teaching Mathematics," includes chapters entitled: (1) "Teaching Mathematics: Reflections and Directions"; (2) "Exploring What It Means to Do Mathematics"; (3) "Developing Understanding in Mathematics"; (4)…

The "Curriculum and Evaluation Standards for School Mathematics" (1989) 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. The document not only addresses what mathematics students should…