A common goal for mathematics teachers at any grade level is for "all" students--not just future mathematics teachers--to develop deep understanding of the mathematics they are learning and using. To that end, this lesson can be used in an upper-level high school mathematics course to introduce the concept of a radian in a way that…

The implications of Earth's ocean being little explored may not be immediately evident to individuals who are not ocean literate. For this reason, initiatives to improve ocean literacy must articulate compelling reasons for ocean exploration. A lesson plan that addresses this issue has been developed as part of the education and outreach program…

The author and his first-year algebra students explored the quadratic behavior behind the parabolic shape of fountains at the local family splash park. This hands-on discovery project has three main parts: (1) gathering data by experimenting with and photographing the fountains; (2) analyzing the photographs to obtain numerical data; and (3)…

Some examples for investigating shapes in the environment are given. Circular objects, triangulation, symmetrical designs, and further investigations are listed. (MNS)

Relationships among the sides are developed for right triangles whose sides are in the ratios 1:3, 1:4, and 1:5. The golden ratio appears in the results which can be used in secondary mathematics. (DC)

Mathematical concepts occur spontaneously from many topics and can be developed in the framework of cross-curricular schoolwork. Consequently, students can gain knowledge of where mathematics arises and insight about its purposes. (Included are activities dealing with the reflectional and rotational symmetries of automobile hubcaps evolved from…

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)

This article describes an activity in measurement and geometry in which sixth-grade students explore the volume and surface area of a donut. Through calculation, creative thinking, and discovery, the students enhanced their geometric vocabulary and reasoning. (Contains 9 figures.)

Presents three investigations that extend the problem of counting the number of squares on a grid in two dimensions to an analogous problem of counting the number of cubes in a three-dimensional cubic array. (MDH)

Investigates the question concerning the maximum number of lines of symmetry possessed by irregular polygons. Gives examples to illustrate and justify the generalization that the number of lines of symmetry equals the largest proper divisor of the number of sides. Suggests related classroom activities. (MDH)

The focus of this article is patterns and pattern making using geometric figures. Included are sequentially planned activities for K-8 students that help them first to discover the attributes of various figures and later how to combine these figures into patterns. Finally, this information is applied to real world activities such as quilting and…

Presents a cooperative-learning lesson in which high school students visit stations equipped with different tools to establish the midpoint of a Pixy Stix, a brand of candy-filled straw. Provides solutions for two potential stations, suggestions to extend the activity, and two activity worksheets. (MDH)

Utilizes LOGO to teach the concept of inequalities by programing the turtle to take random walks in the coordinate plane restricted to predetermined regions defined by inequalities. The students task is to discover the inequalities that define the illegal areas into which the turtle must not move. Provides examples and corresponding computer…

Describes two investigations suitable for grades seven and eight that explore the properties of the figure created when the midpoints of an equilateral triangle or square are joined. (MDH)

Examples of composite functions present students with intriguing questions that they can explore using calculators and computers, geometric and algebraic methods, and approximation techniques. Student-centered activities allow students to make discoveries about functions. (MLN)