. . . though for a while it seems that way to 12-year-old Karen Newman whose parents are in the process of getting a divorce. After Daddy moves out of the house Karen plots to bring her parents face to face, sure that they'll make up when they see each other, but when older brother Jeff runs away from home their enusing confrontation only proves the unreality of her hopes. By then Karen has met Val, another child of divorce, who "reads the entire New York Times every Sunday," insists on facing unpleasant facts, and recommends Gardner's Boys' and Girls' Book About Divorce, which Karen too finds helpful. Thus toward the end when Mother announces that she's selling their house, Karen regrets moving but accepts the way it has to be. All of this is told in the first person without solemnity or forced comfort, and Ms. Blume's sharp sketches of 12-year-old quirks and concerns will hold even those who don't share Karen's problem.