THE Northern Ireland exam board has warned schools that some of its past A-level maths questions are so flawed they should not be used in the classroom.
The board has admitted that 36 of the questions set in the past five years should not have been used for exams. It also accepted that six were so misleading that they should not be used at all.
The admission comes after a long-running row between the board - the Council for the Curriculum, Examinations and Assessments - and one of its former scrutineers, who believes that every statistics paper since 1997 has contained serious errors.
James Nicholson, former head of maths at Belfast Royal Academy, is calling for an independent inquiry into how so many sets of papers with errors were put in front of candidates.
He said: "It is astonishing that the board has had to produce guidance outlining errors spanning more than three years on more than a quarter of all questions.
"This is not an issue solely for A-level mathematics. There are serious questios relating to how all the procedures in place for public exams failed to stop further sets of flawed papers being produced."
As a result of Mr Nicolson's original concerns, the board commissioned a report from Gerald Goodall, an independent statistics examiner, who supported many of the criticisms.
Mr Goodall's report concluded that candidates who had taken the statistics papers could have been disadvantaged by the errors.
The board maintains that no candidate lost out but it has implemented the three recommendations: strengthening its team of statistics examiners, withdrawing past papers and issuing guidance for schools.
Earlier this year the CCEA withdrew five sets of A-level maths papers from circulation after concerns about their accuracy and this week sent guidance to around 350 secondaries warning them about the flaws of past questions.
The board's two A-level statistics modules have become increasing popular: more than 900 sixth-formers sat them last year, up from 680 in 1997.