Challenging Preservice Elementary Teachers' Image of Rectangles

Abstract

Preservice elementary school teachers (PSTs) often have difficulty understanding hierarchical (i.e., class inclusion) relationships between geometric shapes. In particular, PSTs' predisposition to place squares and rectangles in separate categories can be attributed to their concept images. Although the larger mathematics community prefers the hierarchical definitions of special quadrilaterals, the concept images of special quadrilaterals such as squares and rectangles that PSTs develop in their early experiences contribute to a preference for partitional definitions. This study examines the benefits and limitations of using the Shape Makers curriculum unit to modify preservice teachers' concept images and their definitions of special quadrilaterals.