Students at a £37,000-a-year independent girls school were taught the wrong text for their exam.
Pupils at Malvern St James Girls’ School, in Worcestershire, realised the error while sitting the IGCSE English literature exam on 15 May.
Headmistress Olivera Raraty apologised “wholeheartedly” for the issue, which affected one section of the exam paper.
The exam board said the school could submit a request for special consideration of students’ marks.
The Cambridge IGCSE is an international qualification.
According to The Independent, English literature students had been studying Spies by Michael Frayn but there were no exam questions about the book.
Mrs Raraty said: “No girl should be disadvantaged by this. Fortunately, all exam boards have procedures in place to deal with this type of incident and we meet the criteria for ‘special consideration’.
“A full internal investigation is under way and we are unable to provide further comment at this time.”
You may also be interested in:
A spokesperson for exam board Cambridge International said: “We recognise that this is distressing for the students involved. We have asked the school to follow our procedures for rare situations like this by submitting a request for special consideration on behalf of the students affected.”
The organisation’s website explains that “special consideration” is a post-exam adjustment made to a candidate’s mark to make allowances for adverse circumstances.
The school is rated “excellent” by the Independent Schools Inspectorate, and The Good Schools Guide described students as “in the main pretty well-heeled”.
Follow BBC West Midlands on Facebook, on Twitter, and sign up for local news updates direct to your phone.
Kit Armstrong: From child prodigy to piano-playing superstar
Nigel Farage’s 400km pro-Brexit march sets off from Sunderland to London
Music show: La Chica, Danger Mouse, Karen O and Foals
McDonald’s: Tom Watson urges chain to drop Monopoly campaign
Christchurch shootings: Sajid Javid warns tech giants over footage
Study reveals the wolf within your pet dog
NHS let me down, says health manager with cancer
Looting, clashes as Yellow Vests seek new momentum