The Trumpet of the Swan by E. B. White

Louis, a romantic swan, is in love with the angelic Serena, but he can't tell her how he feels; he has no voice. When he meets eleven-year-old Sam Beaver, a human friend, he goes to school with him to learn how to read and write. Louis' father also helps out; he steals a brass trumpet for his son. In the end, Louis learns to play, wins Serena's heart, and repays the music shop owner for his stolen trumpet. Here is a wonderful story of romance, friendship, and determination among animals and humans.