https://news.google.com/articles/CBMijgFodHRwczovL3d3dy5uYmNuZXd5b3JrLmNvbS9uZXdzL2Nvcm9uYXZpcnVzL255Yy12YWNjaW5lLW1hbmRhdGUtZm9yLXNjaG9vbC1zdGFmZi1vbi1ob2xkLXN0YXRlLWhlYWx0aC13b3JrZXItY292aWQtb3JkZXItdGFrZXMtZWZmZWN0LzMyOTI3MDMv0gGSAWh0dHBzOi8vd3d3Lm5iY25ld3lvcmsuY29tL25ld3MvY29yb25hdmlydXMvbnljLXZhY2NpbmUtbWFuZGF0ZS1mb3Itc2Nob29sLXN0YWZmLW9uLWhvbGQtc3RhdGUtaGVhbHRoLXdvcmtlci1jb3ZpZC1vcmRlci10YWtlcy1lZmZlY3QvMzI5MjcwMy8_YW1w?hl=en-US&gl=US&ceid=US%3Aen

Anyone on CI attend public school?  Feel free to describe what happened when you had substitutes.

With a few notable exceptions, word that a class had a sub was for some students like piranhas smelling blood.  In high school, certain kids made it their business to leave the male subs. drenched in sweat and the female subs in tears.  After twice being one of two or three students who did not participate in the sub initiating ceremonies, punished for failing to rectify the situation, when I heard a class was having a sub, I’d cut the class.  I’d go to the library, to study hall, or sometimes, just leave the building and return when the class was over.  If I couldn’t come up with a good story, the worst that would happen was that you’d get a “cut” slip sent to your home, easy enough to intercept before it came to my parents.  Dishonest?  Yes, but better than trying to explain my actions to parents who wouldn’t believe it.  
Did learning take place?  Yes, but not of the academic variety. 
Subs who couldn’t control the class rarely returned, so if the absence was for more than a day, as surely the teachers who will be fired or who will resign, what followed was a series of subs, none of whom lasted more than a few days.  A series of subs in a primary grade classroom is even worse. While the lower grade students aren’t quite as bad, one can count upon losing a week’s worth of learning for each day, unless it’s someone who subs, then stays.  
I recall even in fourth grade having a male substitute who went through the day “teaching” the lessons, writing on the board, talking to the kids, and reading from textbooks—-all the while a group of about six children were so out of control that nobody heard a word he said.  I remember giving up in the middle of a social studies lesson on Peter Stuyvesant.  A book came sailing across the room and hit me in the head, cutting me just above my right eye.  I have a scar there to this day.  I couldn’t get the “teacher’s” attention to request to go to the nurse, so I took the girls’ bathroom pass and treated it myself.  There was no hiding it from my parents, but since I didn’t know who threw the book and nobody admitted to it, nothing was done about it.  It didn’t help that my father had a lawsuit against a board of directors of which the teacher’s husband was chairman! That hadn’t yet come to light. I never saw that sub again and the regular teacher returned next day.  
When I was a high school senior, subs weren’t generally called.  An assignment would be given to be done in study hall.  
There were a few exceptions.  There was one sub who used to ignore any lesson plans and take the kids outside for sports or whatever you wanted.  The only rule was to not make trouble.  And then there was Mrs. Scanlon.  One didn’t breathe incorrectly in her presence.  She was a widow with an Irish lilt, who’d raised nine children mostly on her own.  Discipline was her middle name.  Even the druggie kids would show up because she’d actually see to it that nobody left her class without having learned something.  If only the “army of substitutes” consisted of Mrs. Scanlons!