Step by step lab that instructs students to create two parrallel lines and a transversal in Geogebra.(Geogebra is a free website that the students may access. The lab may also be completed on Geometer's Sketchpad)
Students then measure corresponding angles, alternate interior angles, and alternate exterior angles and find that they are congruent.
Students must have an understanding of corresponding angles, alternate interior, and alternate exterior angles before beginning lab. This lab can be used before students learn that when lines are parallel, those angles are congruent.