Now that spring is here, whenever I'm called on to substitute teach a science class, I take the kids outside, and we build a scale model of the solar system. I use one of those large "easy button" tap lights as the sun, and have a set of push pins made up for each of the 9 planets. (Yes, I include Pluto, damnit!) At the scale I have them pace it off, (one regular step for Mercury, two for Venus, a third for Earth) it helps to be on the school's football feild to be able to pace the rest off.
The kids always come away with a better understanding of the sheer size of the solar system... and the problems of travelling to other stars... especially when I tell them, "At this scale, the nearest star system to us, Alpha Centauri, would be in Hawaii."
Number Two: Conform, Number Six! Conform!
Number Six: I will not be stamped, filed, indexed, briefed, debriefed, or numbered! I am a person.