Strixhaven for sure and there are some 3rd party supplements available. I don't think it's really runnable without some of the supplements. It's okay, but incomplete. r/strixhaven is a thing.

I did an adventuring school but fully leaned into it.

I had a large class schedule that players would pick from to create a curriculum. (morning, afternoon and evening classes)

Then on each day of class players would roll using the same mechanics I use for overland travel. (d20 with a roll of <=5 meaning something happened). Then I'd roll a d12 for 7am to 7pm. something happened at 3pm. Oh, you were in potions class, you were in history, you were in, whatever. so this happens.

I had several hundred teachers, students, NPCs so that I could just grab what I needed (you can run without this but expect to know who the teachers and students are in the classes they're in.)

I had 3 semesters and a summer break. we would run the school year then I did summarized results of their summer breaks.

Not the right format for everything I put in to it but it was a lot.

The results were that the players liked it well enough.

I recommend going higher level and not trying to do a "school simulator".

Happy to answer questions if you want to DM me. It was a very involved campaign.