Big schools often mean more bullying; are very impersonal; have cramped classrooms; less scope for varied lessons and trips.
Now for a personal anecdote
:
When I went to a big secondary I found myself with lots of friends, but was incredibly sad because I wasn’t that close to any of them. Plus, I was constantly picked on by the boys in class along with all the other girls. No one cared.
Then, I moved to an indescribably tiny (Year 10 consisted of 8 of us) class of 6 boys and 2 girls including me. Me and the girl loathed each other at first, we just made friends in other years and I spent some breaks and lunches sitting and reading alone. Still preferred 100 times over because it felt more personal and close knit. Eventually the girl and I made very good friends because we were constantly pushed together for everything.
I think having to deal with a limited scope for friendship is much more like real life. If you don’t like the people at your job then there’s little to do but get used to them.