MEMOIRS OF AN EX-PROM QUEEN

MEMOIRS OF AN EX-PROM QUEEN Alix Kates Shulman (Penguin, $12.95) The ex-prom queen of the title is Sasha Davis, a rebellious Midwestern girl who becomes one of the few women in her high school class to make it east for college. In grad school, she marries a fellow student, then trades school for clerical work. Trapped in a loveless union, Sasha has affairs, divorces (much to the horror of her parents), meets a new love, marries him, has two children, and finds this second, more ''modern'' union as difficult, in its own way, as her first. The book made a big splash when it was first published in 1969 -- Sasha, it appeared, was many women. Though it's been reissued with a new introduction by the author, Sasha's story seems more of an interesting relic of another time than a contemporary morality tale. B+