Are you tired of your high school art students complaining that there's nothing to draw? I start out each year by assigning the students to complete a morgue (what illustrators call a visual reference library). It forces them to think of things they may want to create. It gives them a reason to do it. It will always be available if you make space in your room for them to file it. (Note: I kept 120 student's morgues in a portable hanging file box).
This one sided document is ready to be photocopied.