I found this project at www.artsonia.com, a wonderful source for creative ideas.
1.
Each student draws
three lines that tilt a little to each side on a horizontal sheet of paper. These sections will each
represent foreground, middle ground and background in the picture.
2. They draw three simple tree shapes, one extending up from each line. All should be spread out to give the branches room.
3.
The ground lines inside each tree then need to be erased. The students
will then trace all the pencil lines with a black sharpie. Lastly,
the hills, trees and sky are to be filled in with oil pastels. Most
pastels have a dark and light green, orange and yellow and brown, which
may be used to shade each section to give it depth. If you use
water-soluble pastels, you can brush the artwork with water to smooth
the edges between the colors.