Thursday's paper has outraged a number of students and teachers, who claim the paper did not reflect what had been taught through the NSW Board of Studies syllabus.

In particular, staff and students have objected to the non-specific phrasing of questions in section III of the paper.

Holy Spirit College principal Mark Baker said he had not seen anything like this in 34 years of teaching.

"I can tell you there has been a near-mutiny in schools across NSW," he said.

"We had to coax students to continue with the exam. They were in a state of shock and so were the teachers.

"This is not a trivial matter. This could affect students' chances of moving to the next stage of their education."

Mr Baker said he had been approached by a number of angry parents and he had already written a letter of complaint to the Board of Studies.

Holy Spirit student Adam Reich said he and his classmates had been disturbed by the paper.

"I think the exam was very unfair because it didn't test what was specified in the syllabus, it was more based on general knowledge.

"People were very disturbed throughout the exam and as soon as they saw that final section there was uproar. Students were crying.

"It caused a lot of stress to all of us and impacted our ability to study for other exams."

Adam, who received an Academic Excellence Award from his school and was among the top six students in his year, said he felt he had underperformed in yesterday's English exam as a result of the stress.

He now fears his hopes of studying Commerce at the University of NSW, for a which an ATAR of 95.65 was required, will be dashed.

A spokeswoman for the NSW Board of Studies said she was aware of concerns but the paper was within the published exam specifications for the syllabus.

"We very much want to reassure the kids that they're probably worrying more than they need to," she said.

"They've almost certainly done better than they think."