On the first day of class, I hand out a questionnaire to all students as a way of getting to know them. At the bottom it says: "On the back of this sheet, please draw a person, a house and a tree." No further instructions are given. I learn a lot of things about my students and their skills from these initial drawings!
Some students--even highly skilled ones--will draw three separate boxes in which they draw very simple stick-figure or stereotypical representations. I've learned that this can indicate a student who is very organized and methodical in his or her approach to artwork. As he or she learns (or utilizes) technical skills, later drawings become more animated and detailed--without losing precision and control.
Other students approach this by integrating the three elements to create a scene--often using overlapping, perspective and shading to the best of their ability.
Still other students take a highly creative approach--fulfilling the assignment in new and original ways.
These four drawings are but a few of some really, really neat and diverse approaches to the same assignment!