An amiable story concerning a class of third-graders whose biggest problem is that, since they are grouped by month of birth, they never get a chance to celebrate their birthdays in school. Likable protagonist Brittany's other worries are a tiff with her best friend and being heckled by the class tease, who doesn't yet know what a good baseball player she really is. Brittany saves the day and wins everyone's approval by suggesting that the kids adopt and celebrate the birthdays of historical figures. Realistic characterization and amusing plot details here add up to a satisfying, if undemanding, story. Probably only librarians will be jarred by references to the author of Hans Brinker (not a likely book for a contemporary third-grader to read) as ``Mary Dodge.'' Illustrations not seen.~(Fiction. 7-9)