Although it is history, I wanted to "ease" my fragile 8th graders into the subject of the Holocaust. AS chance would have it, it was Dr. Seuss's birthday when I began the unit, so I read "The Sneetches" to the students, as well as "The Better Butter Battle". They made some connections to what they knew of the subject, but still couldn't understand (or believe) how people would follow such craziness.
So I checked out some social studies lessons, and adapted one as follows. As an intro the "Diary of Anne Frank" I faked a grammar game. Each student picked a ribbon out of an envelope and tied it on his/her wrist. 1/2 the class were green, 1/4 were gold and 1/4 were silver. (They thought gold and silver were going to be the "elite".) Green could speak anytime, gold could speak when I or green spoke to them, and silver could speak when gold or green gave them permission. Obviously, tons of rules could be made up to apply. I asked greens easy questions "Name a noun" and they were rewarded whenever they answered correctly, or at least tried. Gold was asked questions that were difficult, but answerable, and only allowed to have a treat every 2-3 times (depending on the supply of goodies) and silver was asked virtually unanswerable questions (Use a conjunction that serves as a preposition in a compound sentence which has flibbertygibbet as the objective complement). Anyway, you get the idea. When all was said and done, I asked the kids (for homework) to write their observations.
Here's the scary part: No one said it was unfair, they only said they were glad/sad about the color ribbon they were given. They learned something uncomfortable about themselves and the world, but they also understand the problems with indifference and going along with the crowd.
As an aside, we discussed "revisionists" who say that the Holocaust didn't happen. I proved to them statistically that no one in the class had blonde hair, although 8 of them did. ("We're looking for blondes, so let's discount the brunettes. We're looking for girls, so let's discount the boys." We ended up with -3 blondes, because brunette boys had been counted twice.) They seemed to understand that they need to be on their guard with such things now.