The Union Grammar School first opened on August 25, 1856 in rented quarters at the Wesleyan Methodist Church on Powell Street, between Clay and Sacramento. By 1860, the church was purchased and reconstructed as a school at the same location. The new two-storied school building had four classrooms, an assembly room, and two rooms for gymnastic exercises and calisthenics. Dedication ceremonies for the new structure took place on September 19, 1860. The school in the new building was already referred to as the San Francisco High School because by that time, it was generally recognized that the course of study was on the secondary level.