Anthea is not Jewish. We see the other characters often mumble about her thin frame and her carsickness, and she is seen seemingly living with Joan and her mother, which implies that she's either got neglectful parents or is an orphan living with her friend. She also doesn't participate in Joan/Sid/Bernie arguments, and Joan is mostly her voice when she wants to complain. But why would Bernie go out with a non-Jewish girl? Shiksa Goddess.
WMG / Carry On Camping
Farmer Giles' campsite is the British equivalent of Woodstock.Farmer Giles likes to claim that he owns the field but probably doesn't, allowing the concert to be held in unowned territory.
The teenage girls at Babs' school heard of the hippie band from the teenage boys they secretly met up with outside the school gates.Miss Haggerd and Dr Soaper's obliviousness to their students' antics when their backs are turned allows the girls to meet up with boys outside the school. The boys introduced them to the music on one of their dates and they've been fans ever since.
Peter Potter had sex with the innkeeper's daughter, but is probably not the father.Charlie points out that there is a story of a traveller that once shared a room with the innkeeper's daughter which makes the innkeeper snap that he's been in that situation. Peter is also revealed to be sexually frustrated because he and his wife haven't had relations in a long time, so he probably had sex with the young woman when he collected the milk for him and Harriet. However, he's probably not the first stranger to do so. Considering how protective the father is, it wouldn't be surprising if she begs male strangers to have sex with her whenever she's alone in the house. It's lucky, in her defence, that she's really attractive.
Miss Haggerd is the Matron from Carry On Doctor.After the traumatic experience with the patients, the Matron left the hospital after Dr Kilmore was rehired, and became the school nurse at Chaste Academy. She was attracted to Tinkle, so she probably agreed to work there because employer Dr Soaper reminded her of him.
There's a school next door to the Chaste school especially for boys.This is probably the reason why two teenage boys can just hang around a school in the middle of nowhere. They might live nearby but it's highly unlikely that an academy where young girls are taught to be proper ladies would be in a populated area where they could be "influenced" by the working-class locals. What better way to keep the youth in check by having a school for girls and a school for boys in a quiet area in England?
The hippie band in the final scene are as big as The Beatles in the movie's universe.The sheer excitement of the Chaste students and the amount of hippies that turn up for their concert imply that they are big enough to have been known by teenage girls in a boarding school that are probably not allowed to listen to music or watch television.
Joan, Sid and Bernie are Jewish. Anthea is not.Joan has an overbearing mother that triple-checks her and her friend before she leaves the house, Sid is quick-thinking, and Bernie's just a nice guy that wouldn't intentionally hurt someone, and they also spend most of the movie arguing. It's also good to mention that Sid, Bernie and Joan's mother are portrayed by Jewish actors.
The pregnant innkeeper's daughter once went to Chaste Academy.Her father points out that he spent lots of money trying to "make a lady" out of her, so she was probably sent to the school at one point.