I went to Whitchurch Grammar where the cane was used very sparingly and you had to do something incredibly wrong to receive it.
4 or 5 boys in my class - if we had had a mass beating- were effeminate, non sporting and so weak nobody ever bullied them. I don’t think these poor guys could have handled corporal punishment without lots of crying, begging to be let off, etc.
Out of interest, what was the errant girl’s punishment in the end? Also, how did her classmates treat her from then on? Was there some sort of revenge against her?
A mass incorrect caning in my school I think would have had repercussions against the school/teachers by parents even in the 1960s. Most pupils were there to learn and get into university; not to misbehave. You only had to see the other parents at parents’ meetings to understand what they were like. Their precious studious kids being caned would generally not have gone down well!