Jamie is full of questions at home; but when he starts nursery school, he clams up—totally. The teacher asks what he'd like to do; other children offer to share; Jamie watches and listens, but is silent until Dad picks him up. Then, as usual, he chatters about his day. On the second day, he joins in—without a word; weeks later, he whispers his secret to his baby sister: ``I don't know why I can't talk at school.'' The baby is the key— when a classmate's tiny brother visits school, Jamie finally opens up: ``I have a baby, too!'' There's an aura of warm acceptance here, while Hafner details Jamie's family and his welcoming school in cheerful illustrations, depicting the preschoolers with humorous affection. A drama that many young ones will recognize as just their size. (Picture book. 3-6)