I can’t remember if I learned that in school, my parents taught me, or I just picked it up.
But I’m pretty sure that I knew by first grade. Because every classroom had an analog clock on the wall, and you were always interested in knowing when school got out at 3:00 p.m.
The old analog school clocks that twitched every minute taught me how time works. They slowed WAY down when the teacher was droning on, sped way up during recess and lunch, and almost slowed to a stop the hour before school was over. Time stopped entirely when Karen sent a brief glance my way, too.
I learned time was very elastic.
I remember the workbooks from 1st grade that taught us how to tell time....................1960-61