Chaos Theory is a cautionary tale, wherein two upper-Northwest high school juniors flee a boring Baptist party in search of drugs. Naturally, they venture into the wilds of Northeast to score, and, naturally, they find themselves in a whole passel o’ trouble: a dealer who wants to “shoot the fuckin’ cojones off both a” them, a couple of unintended deaths, a father who puts on clownish Indian accents. But they have a few things going for them: a girlfriend who cares, one good FBI man, a “preppy disguise.” The moral of the story, of course, is that a whole mess such as this can be avoided if you let your kids grow their own. Or something. Hear author Gary Krist explain it himself when he reads from and signs copies of Chaos Theory at 7 p.m. at Politics & Prose, 5015 Connecticut Ave. NW. Free. (202) 364-1919. (Caroline Schweiter)