The BBC is reporting that students at UCL Academy said they now feared having to defer their university applications, while others worry that they may have to pay about £450 to sit an exam elsewhere.
The Association of School and College Leaders described it as “pretty unethical conduct”.
The school said it has “robust plans in place” to support students.
“In some cases this takes the form of an additional year in the sixth form to overcome whatever barriers there are,” it added.
Zehra – whose surname we are not using – told the BBC’s Victoria Derbyshire programme that she and other students had been emailed during the Easter holidays saying they had been withdrawn from their chemistry exams.
“I have health problems, but they didn’t care. There was no consideration.”
She said she had offers to go to university in September, but now she was facing rejecting these or deferring for another year.
“I already have anxiety and health problems and this made it a lot worse,” she added.
Geoff Barton, general secretary of the Association of School and College Leaders, said it was “pretty disturbing and pretty unethical conduct” by the academy.
“It seems discourteous being done through email,” he added. “All that preparation has suddenly come to nothing.
“Schools will always have entry requirements to attend to, and they will have continuation grades at the end of Year 12 to proceed to 13, but here [the students] have got to the 11th hour and been told this. This seems totally unacceptable.”
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