Ha ha ha, "Saturday school", was chinese class for me. So in the attempt to keep me connected to my ethic roots, I had to go to school Saturday morning to learn Chinese.
It was horrible and the only thing i learned was how to cheat on tests. The very of idea of having a 6-12 year old on Saturday morning sit and memorize (not learn) characters brings chills down my spine.
It could be other things, too, but some schools make students come in on the weekends as a form of detention.
My highschool had Saturday school for only the 4 years I was there. It was for making up for sick days. or being late too many times.
What were some of the things they taught on Sat. school?
how to sit quietly for four hours. It was just a punishment.
If the poster is a Catholic, probably CCD class.
In the south, Saturday detention is also a common school punishment.