I love what a sketchbook can do for a student. I assign one for each week. Gets their minds solving problems and thinking outside of the box.... and practicing! I am constantly trying to come up with new challenges. I also like to get as much art history in front of them as I can, there's no way I can cover enough art history in a class setting. SO, I have this list of 25 sketchbook prompts and each forces the students to look up a famous work - the prompt may ask them to incorporate something about the work in their own drawing, or use it's style, etc. Includes some modern day artists, illustrators, sculptors, and famous painters.