Eastbrook in Dagenham Road has been affected by the GCSE grade changes

The headteacher of a Dagenham secondary hit out at the government’s exams regulator after announcing that five per cent less students at her school achieved the benchmark of five good GCSE grades than originally thought.

Valerie Dennis, head at Eastbrook, Dagenham Road, spoke out as it emerged that councils and colleges across the country are planning on launching a legal challenge over grade reforms that have led to many students missing out on a C in English.

Pupils need five A* to C grades, including English and maths, to go onto further education.

Just 43 per cent of students achieved five good grades last month as opposed to the 48 per cent the school first thought had reached the benchmark.

Ms Dennis said at least 15 per cent of her students who were on track to achieve a C ended up with a D.

Ofqual met with exam boards to look at the issue but said on Friday there would be no re-marking of papers.

Ms Dennis said examination bodies had changed the grade ratios mid-way through the year, meaning that students who took their exams at different times could have performed equally but ended up with different marks.

She told the Post: “They changed the ratio and the students ended up needing more marks to get a C. The grades depend on when you banked your English results.

“There were some students who wanted to go to Havering College, for example. We have taken them into our sixth form but they are having to choose slightly different A-levels as we don’t offer the same range. It’s awful.”

She hit out at Ofqual, the exams regulator, for not ordering a re-grade, and added: “You can’t change something mid stream.”

Robert Clack and Warren schools are also said to have been affected by the changes.

Ofqual’s chief Regulator Glenys Stacey said: “The June boundaries have been properly set, and candidates’ work properly graded.”

The regulator said students who took GCSE English and English language exams in England and Wales this summer would be offered special resits in November.

Ms Dennis added: “The report has done nothing to change the unfairness of the situation. The idea that students can take re-sits doesn’t address the issue.”

On Monday education secretary Michael Gove told BBC Radio 4’s Today programme that the students affected were treated in a way that “either wasn’t fair or appropriate”.