On Frederick Street, across from Kezar Stadium, two mysterious Art Deco sisters, separated by three hundred feet, stand grandly aloof from their modest neighbors.

They are all that remain of Polytechnic High School.

The original Classical Revival school building was constructed in 1911 and demolished in the 1970's. The surviving Art Deco gymnasiums were additions to the original school.

The new school was announced in the City and County of San Francisco Municipal Record, Vol. IV, No. 3, 19 January 1911:

The Polytechnic High School to be erected on Frederick Street between Willard Street and First Avenue will comprise two buildings - an academic building fronting on Frederick and a manual training and shop building facing on Carl street

The exterior design will be purely classic modified to meet modern requirements. The ornamental cornices, belt courses and cast iron work will be simple but ornate¹ and in detail will lean toward French Renaissance. The construction will be of reinforced concrete, steel, brick, and terra cotta with fireproof staircases. The academic building of three stories, basement, and attic will have a frontage on Frederick street of 330 feet and a depth of 81 feet, exclusive of an auditorium which will break back in the center, with an additional depth of 70 feet and a width of 98 feet.