I've done something similar with a few friends and now recently a paying customer. I set up 4 hour photo-walk sessions and each one focuses on one aspect of photography. DOF, exposure, etc....we shoot 2 rolls of BW while on the walk and then I develop them for viewing. The negative shows the hard truth about things like proper exposure and really sticks well. Also, I loan out some $10 35mm rangefinders (check ebay) because not having the "live view" lets them focus more on getting the settings right and composition with the mystery of how the results will be still left in the air. What I mean by that is that with RFs, you really don't quite know, so one must focus more intensely on the mechanics for the right shot. Low depth of field? Stop that sucker down. You get the idea.

Just an example of what I have found somewhat effective.