You're a bit older than me. By the time I was in elementary school (1970-78), we had air-conditioning in the classrooms, in the form of large bulky units built into the wall underneath the windows in each pod-slice. Classrooms were built inside a pair of two story hexagonal "pods," with four slices out of each pod hex being classrooms (divided from one another only via HUGE rolling cabinet units without classroom doors - meaning nobody's class was ever truly get quiet). Of the other two slices, one was dedicated to restrooms and the other housed the access ramps (one leading up and the other down to the single-story common areas of the school).

This school is still there in the middle of town (on what must be *extremely* valuable property these days). It occurs to me to wonder (in these modern times filled with school shooters): do they still have use those reconfigurable pod-slices or did they give their classrooms actual walls/doors at some point?