Alexander Dallas Bache School is a historic school building located in the Fairmount neighborhood of Philadelphia, Pennsylvania. It was designed by Lloyd Titus and built in 1905-1906. It is a three-story, "L"-shaped, stone building in the Romanesque-style. It features a central projecting gable elaborate arched window. It is named for Philadelphia native Alexander Dallas Bache (1806-1867), an American physicist, scientist and surveyor. It was added to the National Register of Historic Places in 1986.