Standing on Chairs and Desks
Robin Williams made the idea of standing on the desk famous in Dead Poets' Society. If your classroom chairs are sturdy enough, or even if ONE chair is sturdy enough, this is a great exercise to illustrate points at a couple of times in the quarter.
When first presenting an assignment which requires students to critique or evaluate an argument (book, essay, film), I find it helpful to stand on top of a chair myself, just for about thirty seconds, to illustrate the idea that the reader of the student essay is not interested in the "original" argument/ book/ essay/ film but rather in the student's ideas about that "original" text. So I compare it to standing on the chair (which = the "original" text) from whence I make my own points and put across my own ideas. It is fun to make parade and, if students wish, to climb on top of the chair just to get the idea of how important one's own ideas are as compared to the chair/ text.
This metaphor then works easily into writing papers which analyze, evaluate, or simply re-think two "original" texts. A compare-contrast essay would be the simplest example. Standing on two chairs involves balance and choices about that balance, such as whether to lean more on one than the other. Again, I stand on the two chairs and you can let students choose whether or not to follow your example.