As a paleontologist, I'm faced with the fact that all of the stuff I work with is whatever didn't decay and rot away. I worked for several years at the UW-Madison Geology Museum both as project assistant, researcher, and tour guide. Our tours are geared towards kids, and one thing kids love is mild gore. So, as a mneumonic for remembering the difference between vertebrates and invertebrates, we had squish-crunch and crunch-squish. Which is what each group would do if they were stepped on. A bit gruesome, perhaps, but it got the point across. Vertebrates, with their bones inside the body will squish before the skeleton crunches. Invertebrates, with their hard parts on the outside, obviously will do the opposite (if they have anything to go crunch in the first place - but we don't find them as fossils, so that's not as much of a concern in a geology museum).
Those of us involved in paleontology can get lost in our own world. One of the things I like about having to give tours to 4th graders is that one is forced to put complex ideas into simple (perhaps graphic) terms.