Science exams 'too easy' with six marks for grade C

In a damning report, which looked at last year's exam entries, Ofqual said there was "evidence that standards are currently too low".

In one case students only needed six marks to score a C grade on a paper, it found.

It is the second time the regulator has warned that GCSE science is not tough enough.

In March last year the regulator published a highly critical assessment of science GCSEs taken by students in 2007 and 2008 which highlighted "serious causes for concern."

Ofqual ordered an overhaul of the qualifications with exam boards told to take immediate action to toughen them up.

But the report, which Ofqual carried out in with DCELLS, the Welsh regulator, says that standards in last year's GCSE science exams were still too low.

It concludes: "The findings of this investigation did not differ significantly from those found in previous investigations, thus adding further evidence that standards are currently too low in GCSE science and additional science qualifications."

The report also concluded that there were differences in standards between awarding bodies.

For both science and additional science GCSEs the papers, and the standard of candidates' work was "acceptable" for AQA, one of England's biggest exam boards, and WJEC, the Welsh exam board.

But assessments for Edexcel and OCR, the other two major awarding bodies in England, demanded too little of students.

It adds: "Across all awarding organisations some grade boundaries were too low to ensure that candidates showed a satisfactory range of knowledge and understanding across the assessed content.

"For example, in some additional science assessments, the boundary mark for grade A was sometimes less than half of available marks, and the boundary mark for grade C was as low as six out of 30 marks in one case."

In November last year, the first half of the report concluded both OCR and Edexcel were more lenient than AQA.

After last year's scathing report, exam boards were told to design entirely new qualifications. But last month Ofqual called for them to be redrafted because they were still not tough enough.

An Edexcel spokeswoman said: "Edexcel are committed to ensuring GCSE science remains a credible, highly recognised qualification."

An AQA spokeswoman said: "It is well documented that Ofqual asked AQA to lower its standards in 2008 to come more into line with the other awarding bodies and that it was AQA's 2008 standard which the other awarding bodies were expected to follow in 2009.

"We are pleased to see Ofqual's continuing commitment to bring awarding bodies into line on GCSE science standards."

An OCR spokeswoman said it made changes to science papers which were not reflected in the 2009 exams featured in the report. She said OCR was discussing its new courses with key members of the science community to develop new exams.