Teaching Geometry Chapter 2- Exploring Triangles

In this chapter, teachers examine definitions and explore properties of particular quadrilaterals. Ways of classifying parallelograms, rectangles, rhombi, trapezoids, squares and cyclic quadrilaterals are discussed. The van Hiele levels of geometric thinking are introduced and teachers apply these levels to consider an example of students’ geometric thinking on a task. The roles of technology in exploring, conjecturing, and proving are highlighted.