The lesson described combines mathematics, science, and literature, and is easily adaptable for use with classes in basic mathematics, geometry, analytic geometry, or calculus. (MP)

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)

Three worksheets are provided to help secondary students explore relationships among the areas of a variety of similar figures constructed on the sides of right triangles. The activity is extended to include the relationship among the lengths of the sides of the right triangle. Included are several student worksheets. (DC)

The purpose of this lesson on classifying triangles is to aid students' discovery of the different characteristics of equilateral, isosceles, and scalene triangles through computer explorations using Geometric Supposer or GeoExplorer software. (MKR)

Discusses six examples that discover supplementary geometry theorems by using three elementary theorems about the relationships between angles and intercepted arcs in circles. Topics in the examples include angles formed by parallel lines and the sum of the interior angles of triangles, convex quadrilaterals, star polygons, and hexagons. (MDH)

Reported are the activities and findings of a geometry study administered in a sixth grade class using a LOGO-based computer environment primarily involving properties of isosceles triangles. A majority of the students progressed from an unfamiliarity with geometric notions to a successful working relationship even with complex geometric…

Presents 14 distinct methods to determine the sine of the angle formed by the line segments joining one vertex of a square to the midpoints of the nonadjacent sides. Nine methods were developed by mathematics club participants preparing for mathematics competitions and the remaining five by faculty members. (MDH)

Presents an activity centering on Baravelle spirals in regular polygons to review and connect a number of algebraic and geometric topics, as well as to involve students in formal calculations, visualization, pattern discovery, series, estimation, and recursion. (MKR)

The purpose of this study was to develop and establish the validity and reliability of an instrument to measure students' attitudes toward geometry. Participants consisted of 264 undergraduate students from two universities, one in the Midwest and one in the Southwest. The instrument is a 5-point Likert-scaled survey consisting of 32 statements…

This article tells the story of an elementary school principal, a former high school mathematics teacher, who uses the geoboard in her work with a group of fifth-grade students. As the investigation of polygons progresses from symmetry to area to perimeter, hands-on applications of advanced mathematics topics such as the Pythagorean theorem and…

There has been a lot of material written about logarithmic spirals of golden proportion but this author states that he has never come across an article that states the exact equation of the spiral which ultimately spirals tangentially to the sides of the rectangles. In this article, the author intends to develop such an equation. (Contains 5…

This article describes how research on children's geometric thinking was used in conjunction with the picture book "The Greedy Triangle" to gain valuable insights into children's prior geometric knowledge of polygons. Exercises focused on the names, visual appearance, and properties of polygons, as well as real-world connections for each, are…

Each ellipse and hyperbola has a circle associated with it called the director circle. In this article, the author derives the equations of the circle for the ellipse and hyperbola through a different approach. Then the author concentrates on the director circle of the central conic given by the general quadratic equation. The content of this…

Three- to six-year-old children (n=28) and adults (n=46) participated in a two-dimensional search task that included geometry and feature conditions. During each of 24 trials, participants watched as a cartoon character hid behind one of three landmarks arranged in a triangle on a computer screen. The landmarks and character then disappeared and…

This textbook covers geometry and trigonometry and presents problems for student consideration. Geometry principles are applied to surface and solid measurement. Tables of logarithms and logarithmic sines are included. [This book was translated from the French of A. M. Legendre. It was revised and abridged by Charles Davies.]