St. Louis has a ton of primary and secondary pre-war schools—both public and private—but due to population loss many of the public school buildings are in various stages of neglect (and more than a few have been lost). In particular, St. Louis architect William B. Ittner, who is widely accredited with revolutionizing school design (https://en.wikipedia.org/wiki/William_B._Ittner), designed most of the turn-of-the-century/pre-war public school buildings in St. Louis. A number of them have been repurposed as apartments and such, and a number are still awaiting rehab. Sticking to secondary schools per the thread, here a few of my faves:

Union Avenue High School (now Soldan High School):





Roosevelt High School:


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Sumner High School (alma mater of many notable African American St. Louisans such as Arthur Ashe, Chuck Berry, Grace Bumbry, Billy Davis Jr., Tina Turner, etc.):





Cleveland High School:





McKinley High School:





Yeatman High School (later Central High School—sadly, it resides in a very disinvested part of North City):


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There are also a number of lovely old Catholic high schools throughout the city. One of my favorite is the former St. Elizabeth's Academy (Catholic, Sisters of the Most Precious Blood, now the International Institute of St. Louis—center of aerial view below) nestled in the Tower Grove East neighborhood not far from Roosevelt (top right corner of aerial view below):





St. Louis University High School (Catholic, Jesuit)





Villa Duchesne High School (Catholic, Society of the Sacred Heart):


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