DEFINITELY COOL

Roxanne's exhilaration as she faces seventh grade is tempered only by her penchant for worry. While her number one homegirl, Maxine, is off to a private school on scholarship, Roxanne and others from their Bronx housing project go to public school in nearby Riverdale. Roxanne does win new friends, but keeps trying to nail down which behavior is ``cool'' and which isn't: whether to break her mother's rules about guests in order to keep the interest of an eighth-grade boy; whether to cut class for a party as the other girls in her ``group'' do. This time out, Wilkinson (Ludell, 1975, etc.) slips issues of race and economic stereotyping into well-worked territory. Familiar school-story trappings are made fresh by the setting (housing projects are all but ignored by YA writers, with the exception of Walter Dean Myers), and by an appealing, pell-mell narration peppered with exclamations marks that further hasten the pace. Readers who haven't gotten the point by the last paragraph will find somewhat clunky clarification there. Nevertheless, Roxanne's honesty and zeal, the affectionate bumbling of her longtime friend Rolland, and a liberal dose of contemporary slang make for an easy, timely slide through the first days of junior high. (Fiction. 11-13)