When I started school around 1960, there was no air conditioning at school. Ceiling fans, sometimes portable electric fans, and open windows were available, and water (drinking) fountains to help keep cool. By 1970, a large part of the school I attended had been modified with air conditioning units.
was most very welcome. The classrooms were more comfortable and quiet,
and our uniforms didn't stay damp with sweat. We lost something, too. I recall
hearing the twitter of birds, and smelling fresh mown grass during the
end of each school year as summer approached in previous years. This was
less evident as we kept our windows shut. We had once been more in tune
with the climate, the weather and life outside our man-made buildings.
We now in a physical way shut ourselves off from the world around us, and became more and more focused on our world indoors.