Because of the angles and details - planes, trains and automobiles are interesting, but not easy to draw. These guys did great!
Do you see the use of 1-point perspective in the trains?
Along with the challenges (and success!) with drawing, I couldn't resist the opportunity to develop light and dark values and incorporate color mixing into our projects.
In the train pictures, all the gray and brown colors were created by mixing complementary colors (colors that are opposites on the color wheel).
In the airplane drawings, students created some aerial perspective by making the sky darker at the top of the page, and lighter as they approached the horizon line (where the sky meets the ground).
Our last day of class included the opportunity to draw cool cars. Again the kids worked on seeing and drawing the unique angles and details found in their vehicles.