In moments of waiting for other things to happen I've managed to squeeze in some more drawing exercises following the "Drawing on the Right Side of the Brain" book. I'm working on the "negative spaces" drawing section. You're supposed to close one eye to flatten your view and look for the space created by the negative spaces around an object rather than the form of the object itself. It's supposed to bypass our literal tendency to recognize, name, and symbolize things.
I had more than a few minutes in the car waiting for the Philadelphia parking authority to become helpful. Thus I explored the spaces around the barbed wire fence (above). The drawing method felt a little stiff to me, so I also did a version in my usual sketching manner (below).
I thought this might be a good exercise for helping students recognize how objects can be broken down or made up through geometric shapes. So I found an interestingly-posed figure, cut her out of the picture, glued the background to my sketchbook, and filled the positive space with various sized forms which make up the figure.