Schools preparing to teach new maths GCSEs have been plunged into uncertainty by the news that Ofqual has told all exam boards to tear up sample question papers because they have not been pitched at the required standard.

Many schools will have already been using the papers to prepare for reformed maths GCSEs, due to be taught from September. But the exams regulator has decided that three of the boards - OCR, Pearson Edexcel and WJEC Eduqas - have produced sample assessments that are too difficult.

Two of them, Edexcel and Eduqas, produced higher-tier papers so tough that the boundary for grade A would have to have to be set at less than half the available marks.

The fourth board - AQA - has been informed that one of its papers is too easy.

All four have been told to produce revised papers, which will then receive further scrutiny from Ofqual. The watchdog’s chief regulator Glenys Stacey said this morning that the new papers would be ready for schools “from the end of June”, just weeks before the end of term.

“This is really making sure that standards are raised in a sufficient, even-handed way,” she said. “And it doesn’t stop here. There will be further work done in the lead up to 2017 [when the exams are first sat] to have as much confidence as we can, like never before, in the standard being set.”   

The news is potentially embarrassing for the regulator because it effects qualifications that had already been approved for teaching. It also raises wider questions over the standards of all reformed GCSEs - deliberately designed to be tougher than existing GCSEs - being phased in from next year.

Moreover, the problems only came to light because of concerns raised by some of the boards that the AQA sample assessment was too easy. This led to Ofqual mounting an extensive investigation into standards in all four boards’ maths GCSEs, involving mock tests with 3,865 pupils and scrutiny from PhD-level mathematicians.

Ofqual said this morning that it would have to scrutinise actual exam papers for the new maths GCSEs before they were sat in 2017, which would be the first time this has happened.

It has also suggested that it will have to mount similar wide-ranging investigations into the standards of assessments for new maths A-levels and new GCSEs and A-levels in the sciences.

Former education secretary Michael Gove specified that reformed GCSEs should be tougher than existing ones. And it is that stipulation that is likely to have led to three of the four boards producing higher-tier papers that Ofqual found were not “accessible to the full range of ability” of the pupils who would take them.

The regulator said both the difficulty of the maths involved and the way the questions were worded had contributed to the problems. 

AQA chief executive Andrew Hall said:  “We’re pleased that Ofqual has recognised that our qualification works properly as an assessment - allowing us to set reliable grade boundaries which will ensure that students get the results they deserve.

“Teachers can be absolutely confident that the approach we’ve taken all along is the right one. We’re happy to make the small changes Ofqual has asked for - and we’ll do this quickly so schools can get on with teaching in just a few months’ time.”

Pearson UK president Rod Bristow also welcomed the research, which he said “reaches conclusions about standards very similar to our own research last year”. “Ofqual have asked all awarding bodies to make changes to their sample materials, which we will be submitting to the regulator for approval by the end of the month,” he added.

Mark Dawe, OCR chief executive, said: “We appreciate Ofqual’s determination to ensure that all awarding bodies’ exams are of the same rigour. We also welcome the regulator’s commitment to enable new sample exam papers to be with schools and colleges from the end of June.”

WJEC chief executive Gareth Pierce said he was “delighted” that Ofqual had praised the quality of its approach to assess problem solving in maths.

“The overall research findings allow us to refine our sample assessments,” he added. “In response to Ofqual’s request, we will adjust some of our questions so that we move towards the middle ground in terms of relative difficulty. We have already identified ways of making selected questions more accessible without changing our assessment style.”