Yeah, Polytechnic was literally right across the street from Kezar. We used to have to do our laps in gym class around that place. Often we ran into (also literally) 49er players as they went to and fro, although they did all their training inside Kezar. I graduated in June '62, went right into Air Force, got married, etc., etc. Some of the first Dirty Harry was filmed in Kezar. Poly was a great school and had a lot of notable alumni (as which longtime school doesn't of course): George Seifert, longtime 49er (head) coach graduated a few years before I did. The actress Vonetta Magee was in my homeroom, although she was 4 years older, apparently had been home schooled while grooming her modeling and acting career.  You wanna talk about "GORGEOUS?!?!"  Sadly she perished from cancer a couple years back.

Funny thing several of the teachers there were actually published authors under various pseudonyms, which I only learned years later. The Polytechnic buildings were ruled "not earthquake safe" circa 1966-67. The main building still stands and was retrofitted - I think - but all else demolished and the franchise became McAteer High over on the other side of town.