PUPILS must not be penalised by a decision to pull GCSE computer science coursework worth a fifth of the final mark, it has been urged.
Tasks to be completed as part of a course offered by English exam boards were posted online, as well as detailed solutions, according to the watchdog Ofqual.
Most Northern Ireland pupils sit exams set by the north's board, the CCEA, but hundreds also take papers with English boards including AQA and OCR.
The non-exam assessment, intended to test pupils' programming skills, was worth 20 per cent of the total GCSE computer science mark.
Pupils due to take their exams in the subject this summer were able to start their coursework from September last year.
But shortly afterwards Ofqual became aware that tasks and solutions were being discussed in online forums.
In one case, an individual asked for help with a task on designing a piece of software. The first response to this question included a full solution, Ofqual said, adding that the post had more than 2,500 views.
In another, Ofqual said a simple search for a key requirement of a task on a popular online developer community returned more than 40 pages of results.
Writing to students, Ofqual said the decision had been made "with reluctance" but "we do not want anyone to have an unfair advantage".
"While not contributing to your grade, the task will continue to be an important part of the qualification," said Ofqual's director for general qualifications, Julie Swan.
"Learning about a high-level programming language and having the opportunity to show that you can use it to solve problems is an important aspect of a computer science course of study."
The change affects students due to sit the exam in 2018 and 2019.
Sinn Féin education spokeswoman Karen Mullan said every step must be taken to ensure that pupils do not suffer.
"Lessons need to be learned from this episode and every possible measure taken to ensure that flaws in the GCSE assessment process do not penalise students and that the integrity of the GCSE process is maintained," she said.
The SDLP's Colin McGrath said there needs to be a review.
"GCSEs are a very intense and difficult period for young people. This kind of disruption will only add further pressure to those students preparing for exams and will appear grossly unfair to those who approached the coursework in good faith," he said.
