Janie Tannenbaum is noisy and brash and very much with it--a disruptive force and a down. Courtney-Ann Schaefer is ladylike and reticent--a reader of fantasies who lives in their world. But because both fifth graders have scoliosis, or curvature of the spine, they are roommates in a big-city hospital awaiting body-casts and corrective operations. And in that confined, cut-off setting, Janie soon incites Courtney to revolt (unwanted food goes out the window, a daring foray to the coffee shop nets ice cream cones), while Courtney apprehensively lets Janie in on her fantasy world and its rituals. The girls' developing intimacy, and outreach to one another, is handled with more delicacy than the initial conflict-of-personalities might suggest. When Courtney goes first to get her body cast, and her beautiful long blonde hair must be cut off, she asks to have it braided and to have Janie with her (""I'm not very brave, and she is""); the words that Janie reassures her with, though, are their secret words, and she leaves the room with the ""long silky braid"" in her pocket. Then, when they're both in casts--like two ""turtles""--the combination of hijinks and mutual compassion is moving without being maudlin. An attempt to pair up the nicest, prettiest nurse with an understanding, very handsome doctor, prefaced by a poll of the staff on ""love,"" is fluff by comparison--but it has a satisfactory, you-can't-make-it-happen ending. Once the two girls connect, indeed, the story proceeds--buoyantly?--from the mesh of their personalities and the inevitabilities of their situation.