About five years ago, I bought a delightful set of slang flashcards that I found at the bookstore. You can also find them at this website, www.knockknock.biz.
The box says, "Are you over thirty?" (yes) "Nerdy, uncool or just plain white?" (hey...) "Get hip in mere days!" (okay)
I'm telling you, this is hilarity in a box. When I bought them, I was with a teenager. Her 15-year-old wisdom added to the fun. She looked at some of the words and announced, "We don't use that anymore." I have two points regarding these cards.
A) Buy them because you'll hurt your ribs laughing. Each feature a definition and a picture of an older couple or children trying to use the word correctly.
B) Minimize slang in your writing, as it will immediately date the work, unless that's your aim. In which case, Word.