GCSE passes up, but top grades down
GCSE grades A* to C have risen slightly this year, but top A* and A grades have edged down.
Hundreds of thousands of teenagers in England, Wales and Northern Ireland are receiving the results of summer exams.
In broadly stable results, the proportion of A* to C grades rose to 69%, up from 68.8% last year, but A* grades fell by 0.1 percentage points.
Head teachers' leader Brian Lightman has warned of "volatility" in results for some individual schools.
But Michael Turner, director general for the Joint Council for Qualifications, said: "At a national level there is very little change in this year's results but we do see educational policies continuing to have an effect on entry patterns and results at a subject level.
"This is particularly the case in English, mathematics and the sciences."
Education Secretary Nicky Morgan welcomed the results in England as evidence that "a generation of young people from all backgrounds are now securing the GCSEs that help give them the widest range of options later in life - whether looking for a rewarding job or a top apprenticeship".
The best results were achieved in Northern Ireland, where the proportion achieving A* to C grades rose by 0.7% to 78.7%. In Wales, the proportion was 66%, the same as least year.
Across England, 68.8% of entries gained an A* to C grade. But there wide regional variations. London has the best results, with 72% achieving A* to C grades, compared with 65% in the Yorkshire and Humber region.
Labour's shadow education secretary Tristram Hunt described the regional achievement gap as a "worrying trend".
He said that "children in the north and midlands are again being left behind".
In a school near Wakefield there was more drama than expected, when firefighters had to put out a fire at the Freeston Academy, in Normanton, when students were gathering to get their results. There were no reports of any injuries.
Maths and English up
The results published on Thursday show grades for more than five million GCSE entries.
In the core subjects, English and maths results have both improved. In English, A* to C grades increased 3.7 percentage points to 65.4%. In maths, those achieving a C grade or better increased from 62.4% to 63.3%.
There were improvements in A* to C grades for physics, chemistry and biology. But fewer pupils taking the double science GCSE achieved good grades.
The numbers of exam entries for separate sciences - physics, chemistry and biology - had all fallen.
Exam boards say that this year's results have been influenced by the changing age ranges of those taking GCSEs.
The government has discouraged schools from entering younger pupils for exams, so fewer 14- and 15-year-olds are taking GCSEs early. At the same time, a policy of requiring pupils to re-sit maths and English, if they failed to get at least a C grade, means more 17-year-olds are taking the exams.
Another trend identified by exam boards has been the continuing decline in pupils taking GCSEs in modern languages, with falling numbers in French, German and Spanish.
Mr Lightman, general secretary of the ASCL head teachers' union, said it was important to recognise the hard work and achievement of pupils and their teachers.
But he warned that "there is a lot of uncertainty" among head teachers about the reliability of exam grades.
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"Heads are seeing results they just don't understand," he said. "Confidence is wavering."
Mr Lightman said that he had heard of falls in double digit falls in maths results
"We have heard from a number of schools that there are some results, particularly in maths, which were unexpected, and did not reflect the school's knowledge and assessment of those pupils."
He said schools and pupils needed to be able to understand what was required to achieve grades.
"It is devastating for a student who has been on course for a certain grade to miss what they were expected to achieve and it is mystifying to their teachers. It can seriously affect the life chances of students."
The National Union of Teachers' leader, Christine Blower, said the emphasis on traditional academic stories should not undermine the importance of creative and vocational subjects.
"It is vital that we do not send the message to learners that areas such as performing and creative arts, design and technology, PE or vocational subjects are of lesser importance."
There have been warnings from head teachers about confusion facing pupils after they receive their GCSE results, with not enough clarity about the separation of AS-levels and A-levels from this autumn.
Dame Joan McVittie, head teacher of Woodside High School in north London, said: "The information just isn't out there."
Geoff Barton, head teacher of King Edward VI School in Bury St Edmunds, said: "I'm not surprised that so many students and their parents feel bewildered by such a five-year welter of reforms, pronouncements and tinkering."
This year group will have taken fewer public exams - and will face fewer from next year - than any other in recent times.
Next year, they will become the first year without AS-levels in some subjects and, because of a teachers' boycott five years ago, many of them did not take Sats tests at the end of primary school.
There have also been calls for GCSEs to become a less high profile exam, when young people are now required to stay in education or training until the age of 18. CBI chief John Cridland has argued for GCSEs to be scrapped.
But the government has signalled that it will push for higher grades at GCSE in England.
In the wake of the general election, plans were announced to improve "coasting" schools, with new targets that will require 60% of pupils to achieve five good GCSEs, including English and maths.