Continuity: Whilst they are deciding how to raise the money, Number 4 - Kidnapping, or K.Nap - is there in one shot, then vanishes, then reappears with another option (Blackmail, or B.Mail) in number 5 that has not been there previously.
Factual errors: When Cheltenham Ladies College arrive on their school bus to play hockey, Cheltenham is spelt wrong on the side of the bus - spelt Chelteham
Continuity: The bank manager gives Miss Fritton four weeks to raise £500,000 to avoid the school being foreclosed. However, at the School Challenge final, Chelsea says she has been preparing for the show for six weeks, despite entering the competition only as part of a plan to get the money to avoid foreclosure.
Errors made by characters (possibly deliberate errors by the filmmakers): In the School Challenge final, the answer to the question "What is the volume of a sphere?" is given as pi r³, both by the show and the school bursar who says he's always been good at maths. He's not THAT good, as the volume of a sphere is actually 4/3 pi r³.
Errors made by characters (possibly deliberate errors by the filmmakers): The first time Geoffrey Thwaites is looking round St Trinians, he dips his index finger into the glass of vodka but licks his middle finger.
Revealing mistakes: There is one shot where the Goth girl, whilst dancing to avoid the security beams guarding the picture, puts her leg through a beam but nothing happens.
Continuity: At the shooting range, the teacher with the machine gun shoots the heads off several of the "ducks". But when the girls with ducks on their heads come up, a second later, all three ducks are intact.
Continuity: When the girls are crawling back along the cable, there is a shot from just in front of Steven Fry which shows them behind him, when every other shot shows that the cable is over the audience.
Revealing mistakes: When the first years are styling Anabelle, two of them are shown using brushes. But, when they show Annabelle's face, the arms styling her clearly belong to larger/taller people.
Continuity: When Flash comes to see what the girls are selling the number plate on the car says GU06 SBX, but when he leaves after the girls have given the car a 'paint job' the number plate is BN 0413.
Incorrectly regarded as goofs: When Flash rolls in in his black car his registration plate reads "GU06SBX" whereas after the paint job to make it silver the plate reads "BN0413". However the girls have changed the plates because the car was most likely stolen, which also explains the paint job.
Errors made by characters (possibly deliberate errors by the filmmakers): When the teacher gets off the Cheltenham Ladies' College coach and talks with the minister, she says: "Between you and I..." No real CLC teacher would have perpetrated that glaring grammatical mistake.
Revealing mistakes: When Kelly suggests stealing the painting when the girls are brainstorming with Flash, the 'Posh Tottie' girls react by signing 'Oh my God'. However, the girl on the left makes the 'Oh' sign with her hand too early, and tries to hide her grin.