Alf Coles and Barry Orr reflect on what it looked like when Alf taught a year 7 lesson. In this article, Alf was asked by Barry (student) if he would take a lesson with the Y7 class that he had taken over from another teacher in the department in order to see what someone else might do with his lesson plans. Alf describes what some moments with…

In his famous quadrature of the parabola, Archimedes found the area of the region bounded by a parabola and a chord. His method was to fill the region with infinitely many triangles each of whose area he could calculate. In his solution, he stated, without proof, three preliminary propositions about parabolas that were known in his time, but are…

Within statistics instruction, students are often requested to sketch the curve representing a normal distribution with a given mean and standard deviation. Unfortunately, these sketches are often notoriously imprecise. Poor sketches are usually the result of missing mathematical knowledge. This paper considers relationships which exist among…

Using the power series solution of a differential equation and the computation of a parametric integral, two elementary proofs are given for the power series expansion of (arcsin x)[squared], as well as some applications of this expansion.

This article describes explorations using The Geometer's Sketchpad for algebra and calculus content.

The geometry textbooks of the new system of secondary education in Iran differed dramatically from the old ones considering the aims, the visions, the content, the approach, and the educational purposes. Four hundred eighty mathematics teachers participated in a nationwide professional development program conducted by the author to facilitate the…

This article begins with a comparison of two groups of teachers, working on the same tasks in Analytic Geometry. One group has only basic experience in CAS-assisted problem solving, and the other group has extensive experience. The comparison is discussed in terms of the interplay between reflection, operative knowledge and execution. The findings…

The interpretive framework for the study of learning introduced in this article and called "commognitive" is grounded in the assumption that thinking is a form of communication and that learning mathematics is tantamount to modifying and extending one's discourse. These basic tenets lead to the conclusion that substantial discursive change, rather…

In this article, the author describes a 200-year-old ladder problem that can carry learners to high levels of mathematical thinking and activity. This problem requires learners to go from a word problem to an equation to a graph and from there to a solution. As this problem of specifics is turned into a problem using variables, technology,…

Mathematics is both a beautiful language and the simplest systematic discipline men ever created. The simplicity of mathematical concepts almost guarantees that the facts it establishes about those concepts will also be elemental. Despite this simplicity, most people complain about the difficulty of mastering the subject and shun the study of…

Quilters have been practicing geometric principles for centuries. Since straight seams are easier to sew than curved ones, the grid naturally evolved as the basis for their designs. This book is a resource for experimenting with traditional patchwork quilt patterns. It provides students a hands-on understanding of geometric concepts. It contains…

This book contains 40 lessons in problem solving divided into five chapters. Chapter 1 contains several lessons in which solutions are derived through investigation of numerical patterns. Chapter 2 contains lessons in which problem-solving situations are presented in a graphical context. It also includes two lessons in which students construct…

Calculation of the percentage of work completed when the edges of jigsaw puzzles have been assembled provides interesting problems. (SD)

Several excerpts from Euclid's "Elements" are cited, and their applications to the natural, positive rational, and positive real number systems are discussed. (SD)

Geometric analysis of a cube can motivate formulae for factoring algebraic expressions involving sums and differences of cubes. (SD)