Helping Students Discover Total Internal Reflection part of Interactive Lectures:Examples
Students learn the basic relationship of Snell's Law, practice applying it to a situation, then are given another situation where it "doesn't work."??? This situation turns out to be one in ...

The Magic of Optics: Now you see it, now you don't part of Teaching with Interactive Demonstrations:Examples
A magical demonstration where a Pyrex tube vanishes in a beaker of mineral oil. Useful demonstration to introduce to concept of refraction (and/or partial reflection).