I teach three classes at a state university, Photojournalism, Digital Photography, and 35mm B&W film Photography. In that B&W film photography class, we go over a quick dissect of the zone system. We dont need densitometers. I just have my students experiment with shooting one roll of B&W film, overexposing for the shadows in a scene with both dark shadow tones and bright highlights , and then I have them underdevelop that roll. They also have to shoot another roll at the "averaged" exposure their camera meters give them of the same scene and develop that roll normally.

They get to see the effects of this simple lesson into the zone system when they print these negatives in the darkroom and see the greater tonal range possible.

Cheers and best to you.