Khan Academy
Khan Academy: Draw Parallel and Perpendicular Lines
Practice drawing parallel and perpendicular lines, line segments, and ray. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
PBS
Pbs Learning Media: Math + Arts: Perspective Drawing
In this lesson, students use line segments, angles, and parallel and perpendicular lines in order to create a one point perspective drawing.
National Council of Teachers of Mathematics
The Math Forum: Lines and Slope: Chameleon Graphing
Join Joan the chameleon in an exploration of lines and slope. You'll be drawing lines, calculating slope, using equations and more!