Explains how conic sections can be approximated by paper-folding activities and proves why they work. (Author/NB)

Presents student solutions to a problem using different strategies that focus on kitchen geometry. (YDS)

In this story of a teacher-designed activity called Garage Math, 5th grade students broadened their understanding of how mathematics is used in the real world and strengthened their mathematical skills as they assumed the roles of construction workers. (Author/NB)

Presents a variety of activities in which 4th grade students investigate prisms and pyramids by building models from folded paper and drinking straws. (Author/NB)

Presents the Shape Search problem to develop student visualization. Focuses attention on the National Council of Teachers of Mathematics (NCTM) Geometry Standard. (Author/NB)

Suggests an alternative proof by analytic methods, which is more accessible than rigorous proof based on Euclid's Elements, in which students need only apply standard methods of trigonometry to the data without introducing new points or lines. (KHR)

Describes a college geometry course centered around challenging, open-ended problems that invite students to draw upon their experiences and share their understandings. Includes discussion of sample problems; writing assignments; classroom dialog; student comments and insights about geometry, mathematics, and themselves and mathematics; and…

This paper advocates the use of symbolic computation packages as another aid in teaching geometry. The need for such packages and their use in computerized proofs are demonstrated by a problem in high school planar geometry. (LZ)

Using sequential chains of regular n-gons in a row with one side touching, as for example, one triangle, two triangles, three triangles, and so on, students graph the length of the perimeter versus the number of n-gons and determine the functional relationship for different values of n. (MKR)

Standard treatments of uniform circular motion generally employ a combination of geometric and kinematic arguments to obtain the magnitude of radial acceleration. Presents a novel approach to the geometric portion of the derivation that uses the property that vectors can be translated parallel to themselves. (JRH)

Maintains that, by looking at and asking questions about the shapes of common objects, teachers can lead students to discussions of geometric topics such as triangles, tessellations, point on plane, and conservation of space. (MDM)

Presents an activity using simple constructions and a knowledge of proportions to discover that the sets of points generated by the described procedures are circles. Presents a proof of the result. (Author/MKR)

Presents proofs of some trigonometric identities from a geometric point of view. (MKR)

Describes an analysis of the direction taken by a baseball immediately after coming into contact with the bat. Uses geometry, trigonometry, and physics. (MKR)

Presents results from research aimed to design and experiment with a set of units for teaching plane isometries in grades 3 through 12 and applies the van Hiele model of geometric reasoning to isometries. Includes a table of characteristics of teaching objectives for the van Hiele Levels in Isometries. (MKR)