Sounds like the parochial schools I went to!
Yup. And most of the sisters probably had little more than high school diplomas themselves.
My BIL attended a parochial school in NYC. There were 40-50 kids in his classes.
I had 50 to 65 students in my parochial school classes. Discipline was very strict by today’s standards.
And I bet your BIL turned out just fine! I keep saying, bring back the fire & brimstone! Stay safe.