I set up some oranges and plastic eggs, side lit by a clear light bulb, all other lights off and blinds closed. This was so the students could clearly see the way that the objects were illuminated on the lit side,dark on the unlit side and the shadows cast.
They used the big fat writing pencils that are considered best for learning in this country; I chose them because they have nice leads that can achieve a range of grays, and are good for side or normal grip when drawing in the shading.
At some point after the middle of the session I showed them a black & white photo of the still life. But I really wanted them to see through their own eyes and focus on light, dark, and mid tones.
