This lesson unit is intended to help teachers assess how well students are able to: work with concepts of congruency and similarity, including identifying corresponding sides and corresponding angles within and between triangles; Identify and understand the significance of a counter-example; Prove, and evaluate proofs in a geometric context.

This lesson unit is intended to help teachers assess how well students are able to produce and evaluate geometrical proofs. In particular, this unit is intended to help you identify and assist students who have difficulties in: interpreting diagrams; identifying mathematical knowledge relevant to an argument; linking visual and algebraic representations; and producing and evaluating mathematical arguments.