Molly Riordan and Ella Gant (left) celebrate after collecting their GCSE results at Norwich School

The number of students receiving the top GCSE grades rose for first time in seven years despite major reforms

The proportion of entries scoring a C or above – or a 4 under the new grading system – increased by 0.5 percentage points from 66.4 per cent last year to 66.9 per cent.

Tens of thousands of teenagers received their GCSE results in England, Wales and Northern Ireland amid major exam reforms.

Last year, the GCSE pass rates fell and the number of pupils attaining the top grades dropped to the lowest point in a decade.

Grades were awarded in the new tougher GCSE subjects – maths and English – last summer. Students in England received the new numerical grades in a further 20 subjects this year.

Headteachers have raised concerns that the new GCSE grading system sends a "demoralising message" to students who are likely to score lower results in their exams.

The Association of School and College Leaders (ASCL) said it had concerns about pupils performing at the lower end of the grading scale.

"Our concern, however, is over those pupils at the other end of the scale who are taking exams which are harder than their predecessors and who have been told by the Government that a grade 4 is a 'standard pass' and a grade 5 is a 'strong pass'," Malcolm Trobe, ASCL deputy general secretary said.

"That is a very demoralising message to those who achieve grades 1, 2 and 3, and the new system does not work very well for them at all."

See below how we covered GCSE results day

A-level results 2018 – in pictures Show all 21 1 /21 A-level results 2018 – in pictures A-level results 2018 – in pictures Students celebrate their A Level results from Ark Academy in Wembley PA A-level results 2018 – in pictures Charlie Jenner, Nathan Sharp and Abhinav Boddu receive their A Level results at Norwich School PA A-level results 2018 – in pictures Students collect their A Level results at Brighton College PA A-level results 2018 – in pictures Students celebrate their A Level results from Ark Academy in Wembley PA A-level results 2018 – in pictures Twins Himmat (left) and Arjun Sohal, who both got 3 A's in Maths, Physics and Chemistry, and will both be going to Bath Universirty to study Chemical Engineering, celebrate their A Level results at Peter Symonds College, Winchester PA A-level results 2018 – in pictures Students celebrate their A Level results from Ark Academy in Wembley PA A-level results 2018 – in pictures Alex Cox receiving his A Level results at Mander Portman Woodward College, Edgbaston, Birmingham PA A-level results 2018 – in pictures Students react as they receive their 'A' level results at Stoke Newington School and Sixth Form in London Reuters A-level results 2018 – in pictures Moyle Oloko with her results at Brighton College in East Sussex PA A-level results 2018 – in pictures Grace El-Mokadem, Maddie Backhouse, Claudia Ballard and Sophie Plumber read their A Level results at Brighton College in East Sussex PA A-level results 2018 – in pictures Twins Emily and Molly Goldberg receive their A Level results at Merchant Taylor School in Crosby, Merseyside PA A-level results 2018 – in pictures A student reacts as she receives her 'A' level results at Stoke Newington School and Sixth Form in London REUTERS A-level results 2018 – in pictures Students react as they receive their 'A' level results at Stoke Newington School and Sixth Form in London Reuters A-level results 2018 – in pictures Simran Kaur Bahia 20 receiving her A Level results gaining an A*, A and B at Mander Portman Woodward College, Edgbaston PA A-level results 2018 – in pictures Students pose for a photograph as they receive their A Level results from from Merchant Taylor School in Crosby, Merseyside PA A-level results 2018 – in pictures Amanda Georgevic with daughter Phoebe Georgevic 19, who got two A's and one B in her A Level results at Mander Portman Woodward College, Edgbaston PA A-level results 2018 – in pictures Students react as they receive their 'A' level results at Stoke Newington School and Sixth Form in London Reuters A-level results 2018 – in pictures Harriet Selway, 17, left, and Niamh Davies, 17, right, both from Horfield, Bristol, react as they open their A Level results at St Mary Redcliffe and Temple School PA A-level results 2018 – in pictures Eleanor Elizabeth Sykes 18 receiving her A Level results gaining 2 A's at Mander Portman Woodward College, Edgbaston PA A-level results 2018 – in pictures A group of students talk after receiving their A Level results at Mander Portman Woodward College PA A-level results 2018 – in pictures A student reacts as she receives her 'A' level results at Stoke Newington School and Sixth Form in London Reuters

Those in Wales and Northern Ireland will continue to receive their grades in the traditional A* to G format.

The new linear GCSEs – which have harder content, less coursework, and more exams at the end of two years – are now being graded using 9 to 1, rather than A* to G.