Ever wonder why your mom and dad (or maybe you) are such a mess? These "discussion posters" from 1973 offer clues. Some are icky ("I'm O.K., and You're O.K."). Some are depressing ("What is the purpose?"). And some are borderline obscene, like this shot of a curious boy with a rocket over his crotch. Check out the entire hilarious collection below. It's a back-to-school special!