Kevin, Thank you for your comments. In a way it's simple if we think like a student. That is, how would I like this material presented if I were a student and needed to learn this material, given the time and resources available to me? Trial and error, experimentation, creative lab applications, etc., etc. Teaching is dynamic. We keep what works and spit out the bones for that which doesn't work. I'll add that not only using more senses in learning, but also getting students to teach the material is one of the best ways for them to learn. It may seem backwards, but I have found (given adequate time to prepare), students learn by this method. I guess its like the old saying, "the teacher always learns the most". Why not apply that to our students? Barry Westling