A Church of England Academy in Darlington has said it will launch an investigation into the sharp drop in students who achieved five A* to C grades in their GCSEs.
St Aidan's Church of England Academy was expecting its results to be in excess of the 44% of passes between A* and C achieved last year.
"At present, we would be declaring a mark of 34%, which is not acceptable and is being strongly contested," said principal Alison Appleyard.
“I simply don’t believe the English marks are correct. We have asked the examining board to review the situation with all urgency.
“We hope that this will be rectified very soon. Until that point, we will not be be in a position to formally confirm this year's examination marks.
"This is a difficult situation not only for the Academy, but also for the students affected. We will be doing everything we can to resolve the situation."
Stephanie Francom, Assistant Principal for Standards, said: “I am concerned in what seems to be a change in exam grade boundaries and this may disadvantage students by limiting their future opportunities. Students should not be used as pawns in a political game, which is what this seems to be to me.
“An illustration of this situation is, a number of students that had been awarded A and A* grades in their English coursework have seen them moderated down to Cs- and that has happened for B and C grades as well - how can that be correct?
"For the last five years we have worked hard to positively improve our performance and reputation, but in a single stroke a politically driven initiative has negated a lot of everyones hard work.”
The Rev Canon Sheila Bamber - Chair of Governors said: “The real issue in all of this is that the grade boundaries have changed between January and the June exams and that wasn’t communicated, or if it was, not clearly.
"We started this academy to give students in this area the best possible life chances and this doesn't help us deliver that. I am very disapointed, but we will strive to overcome and move forward."
There was an overall fall in students being awarded an A* to C grade across England, Wales and Northern Ireland, from 69.8% last year to 69.4% this year.
The proportion of students attaining an A* or A grade also fell from 23.2% to 22.4%.
The fall in grades was most acute in English. In English literature, the percentage of students graded A* to C grade was down from 78.4% last year to 76.3% this year. In the English language and combined English literature and language exams, there was a drop in A* to C grades from 65.5% to 64.2%.
The dip comes after the steady rise in students gaining an A* to C grade over the last 24 years prompted suspicions of grade inflation.
CofE Academy questions GCSE results
Published 23 August 2012