Sometimes its hard to know how to form a composition. We start drawing and worry so much about the individual pieces of a thing, and forget to worry about the way it might sit in the picture plane. Artists sometimes use view finders to solve that problem.
In our third grade classes we took re-purposed old school x-ray frames, taped overhead projector paper in them and traced the world around us in the frames. It was like taking a very slow photograph, but just the outline. After tracing, we created finished works of art in watercolor and colored pencil. It was a simple but effective exploration of composition.