Cooperative groups were given transparencies of eight regular inscribed polygons and overlays of corresponding circumscribed polygons and were asked to find the perimeters and ratios of perimeter to diameter. Transparencies give students a graphic illustration of limits. Includes reproducible worksheet. (NI)

Children 3.5 to 5 years old were asked to judge which of several possible sets of parts matched a configured target form and to copy the target forms. Found a significant association between age and performance on the perception task and consistency across the two tasks. (MDM)

Introduces a room air-exchange activity designed to assess student understanding of the concept of volume. Lists materials for the activity and its procedures. Includes the lesson plan and a student worksheet. (KHR)

Explores what is involved in the teacher's work of engaging students in producing a proof. Analyzes what teachers do to create a task in which students can produce a proof and what teachers do to get students to prove a proposition. Indicates that traditional, formal, two-column proofs place contradictory demands on teachers regarding how ideas…

Presents three lessons in which Cabri geometry is used. Discusses the pedagogy of those lessons along with objectives and resources. (KHR)

Provides activities focusing on students' use of manipulatives to demonstrate understanding. (Author)

Presents responses to the Mathematics of Motion problem which includes estimating the area of shapes on grid paper. (Author/YDS)

Explores how constructing mazes to race two mice, Thunderbolt and Sweetie Pie, leads to an investigation of geometry and measurement concepts. (KHR)

Presents an overview of the 6-8 Standards and their rationale. Demonstrates the need for a cohesive mathematics curriculum. (YDS)

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)