Click on the green flag and watch the mouse draw three sets of parallel lines. See: Angle Mouse http://scratch.mit.edu/projects/16793255/ Perpendicular Mouse http://scratch.mit.edu/projects/20186064/
This is the third in a series of basic geometry projects exploring the idea that programming a concept from geometry is a measure of how well one UNDERSTANDS the concept. The other two projects are: Angle Mouse http://scratch.mit.edu/projects/16793255/ Perpendicular Mouse http://scratch.mit.edu/projects/20186064/ In this project the mouse draws a line, backs up 75 steps, raises the pen, turns left 90º, moves forward 75 steps, turns right 90º, drops the pen, and draws the line parallel to the first line. An important variation would be to generalize the turn angle. Doing so, one will be led to the fact that if parallel lines are cut by a transversal, corresponding angles are equal.
