You want late 80s?
At mine they finally allowed trousers for home clothes on weekdays in 1985, previously only allowed on weekends and jeans had been forbidden. Only juniors (Y7 and 8)changed after lessons, everyone else just wore uniform all week. Sunday uniform for Chapel.
My friends' brothers went to boys boarding schools at the same time and mitzi's stories are not unusual. Girls boarding schools had some outbreaks of bullying but on the whole the girls united against the staff, very them and us.
No actual corporal punishment by then but teachers throwing board rubbers or molecule models was normal, ditto dragging or pushing as needed.
Lessons varied from the excellent to the random (had a year of watching films instead of science every Monday morning, on the understanding we would work extra hard in other science lessons) and the frankly useless - one teacher we just took the mickey out of the entire time and learned nothing of the subject that year. Actually, make that half a dozen teachers... Though as we were generally wanting to pass GCSEs, by fourth year we were tolerant of teachers who were simply 'do exercise a. Now do exercise C on page 113...' and mostly cooperated.
We would do anything to escape the grounds, but doing so without permission was instant expulsion. Well, instant if you weren't going to get good exam results. There were two or three exeat weekends a term when most people went away but about 1/5 would stay and go on trips. Plus anyone who had been gated, which involved signing in with house staff hourly to prove you were there. There were shopping trips from 3rd year each weekend, plus bowling, ice skating, DofE, theatre and cinema... We'd try anything just to get out - now with a tween who goes 'boring' to everything, I can see the attraction. Though we were also experts in hiding booze and fags. Y7 and 8 were tough as shopping trips were only to a village and you were allowed 50p to spend (not enough for 2 chocolate bars) so we all hid money too.
Then, probably half the girls were expat brats, a quarter foreign students from Hong Kong, SE Asia and MEast, and maybe 1 in 10 there because parents were having messy divorces and a similar number because there was abuse in the family and grandparents paid for it, or similar. For some reason lots of girls ended up telling me that kind of stuff. In 6th form we did lights out duty every few weeks and supervised prep every so often.
Unlike the sexual and physical bullying of boys schools, there were rumours spread (half true), but anorexia and kleptomania were rife. Rich girls were usually the thieves. Friendship groups were often related to wealth - I used to get extra cash by buying cigarettes for people and not giving them change. Girls got expelled before they could die of anorexia. There was also a full time school psychiatrist, two nurses, one scary, one nice but incompetent, and the traditional pervy doctor. There was a rumour that male teachers had to be married or gay except for Mr X (an undesirable but sweet chap) - a number of music teachers confessed on their pupils last day that they weren't actually gay/married but just pretended they were to keep hormonal girls off them.
2 to a room for 4th and 5th year, singles in 6th form. Mostly decorated with Smash Hits and Cosmo posters. In 6th form you could usually make excuses for going into town and it was civilised except not being allowed a job 'inappropriate', and could even go out in the evenings on Fri and Sat to 10pm, which could usually be stretched to 10.30. Did mean we only went to the dodgy nightclub which got going early and was where the local drug dealers hung out. Skiving Chapel and PE was feasible by 5th year too.