Presents two ideas to help beginning mathematics teachers. The first presents a way to record and grade homework. The second suggests a manipulative to help students understand the trigonometric concept of reference angle. (MDH)

Can the sum of the edges, the surface area, and the volume of a three-dimensional object be numerically equal? Solutions to this challenging problem are discussed. (MNS)

Discusses techniques to help students in the primary grades discover geometric concepts for themselves, particularly the attributes of circles and polygons. Using examples from real-life situations is suggested. (JN)

Presented is a four-part program for teaching geometric concepts related to the shape of a football. The program includes activities in which students examine footballs, construct a football using isometric paper, examine the "football" versus a regular icosahedron, and investigate planes of geometry. (JN)

Some traditional and some less conventional approaches using the cotangent to solve the same problem are described. (MNS)

Illustrated is how students can be directed to move from a geometric to an algebraic mode of thought and back again in linear algebra, thereby deepening their understanding. Rotations and line reflections in the plane are used as the example. (MNS)

Arrays are seen as excellent models for beginning multiplication examples, but that they are often put aside by teachers when they become unwieldly for greater factors, possibly depriving learners just when they need the help. The use of grids made on paper marked in squares is suggested. (MP)

The process of investigating some of the properties of diagonals and other geometric concepts with a group of 11-year-old girls is presented. Possible changes that could have been made in the lesson are discussed, and examples of individual student work are provided. (MP)

The 1989 document, "Curriculum and Evaluation Standards for School Mathematics" 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. When completed, it is expected that the Addenda Series will…

The author observes that the predictor functions determined geometrically by Ranucci (EJ 090 184) can be algebraically derived, and that capable students might enjoy verifying them. Algebraic formulations and derivations are provided. (SD)

Many activities are described for teaching two fundamental concepts concerning one-half. These concepts are one-half of a number and one-half of the size. (JT)

Some reasons why simple ideas in projective geometry should have a place in the elementary school curriculum are suggested. Then, seven lessons on projective geometry that were taught to a class of 10-year-olds are described. (MNS)

Trademark designs provide a familiar yet innovative way for students to look at a number of mathematical concepts. How line and rotational symmetry can be presented using trademarks is the focus of this article. The emphasis is on the design of bulletin boards. (MNS)

A construction of an ellipse, given its foci and major-axis length 2a and using a compass and straightedge, is illustrated. It is based on Dandelin's elegant proofs that the sections formed by the intersections of a cone with a plane are an ellipse, parabola, or hyperbola. (MNS)

This paper illustrates how to teach parallel perspective using Cabri software. Examples include how to move/present cubes, how to use symmetry to draw a star from triangles, how to modify tessellations, and how to present circles by Cabri software. (Author/KHR)