I took Geometry over the summer between my freshman and sophomore years of high school.
Class was at Shasta High School and I was lucky enough to have two friends with me.
We started around 9am, received instruction all morning, had a mid-day lunch break, more instruction in the afternoon and usually a quiz before we went home.
Our classroom was a portable trailer in the beginning but moved in the Home Economics room partway through the session. The teacher always kicked us out of the classroom during lunch and we were absolutely not allowed back in until the break was over.
I found out why on the day I accidentally came back early.
The teacher always showed up carrying a large hard-shell cooler which, we assumed just had her lunch in it.
It turns out the cooler was full of cans of ODouls non-alcoholic beer. Lots and lots of cans of ODouls. At least a 12 pack, maybe more.
And she had finished all of it.
I don't know if those quantities were enough to get drunk off or what she was getting out of the deal but she had that cooler every day for the entire session.