The Starlight Raven — C. Dale Brittain

Antonia is the daughter of the head of institutionalized wizardry, and she wants nothing more -- or so she thinks at fourteen -- than to grow up to be a wizard too: the first woman wizard. But then she discovers that her mother has all sorts of unexpected female cousins who intend her to come be a witch with them, at the same time as she realizes that a lot of the male wizards are highly opposed to letting a mere girl learn their arcane secrets… As she tries to find her own way, she hears the legend of the Starlight Raven, a bird rejected by its own kind because it does not fit in anywhere, whose appearance is a marker either of doom or of unexpected triumph.