This is one of my favorite exercises, both for myself as a way to get moving and as a subject I teach in workshops. I originally began thinking of a way to loosen up for painting the landscape. I recalled my experiences in life drawing classes, where most sessions began with 30-second gesture drawings. I loved those; in many ways, I thought they were much more fun than longer poses with the figure, and that some of my best work came when I had only 30 seconds to draw and no time to think.
So to translate this to using pastel and painting landscapes from photographs as a class exercise, I came up with the following rules: