More than 30,000 16-year-olds leave school with no qualifications and a further 10,000 scrape through with a single GCSE at grade D or below, a new analysis of government figures shows.

The research suggests that the scale of underachievement at school is far greater than previously thought and raises serious questions about the wisdom of new legislation to raise the education leaving age from 16 to 18.

Michael Gove, the Shadow Schools Secretary, said that the Government’s practice of including teenagers with one GCSE pass at grade D or below in its official figures had created a rose-tinted view of academic achievement in England. For the vast majority of pupils and employers any GCSE lower than a C had little value in the jobs market. “No employer is going to look at a young person with one grade F or G and say, ‘Thank heaven, at least they have got that’,” he said.

Mr Gove said that many of those not gaining GCSEs became disengaged from school at a very young age, often because they had not had the right support at primary school.

The exam figures for last year, obtained by the Conservatives in a parliamentary answer, show that 12,159 pupils in year 11 were not entered for any GCSEs and a further 19,110 failed to gain a single GCSE; 9,881 achieved one GCSE at grade D or below.

John Dunford, of the Association of School and College Leavers, said that almost all of those not entered for exams would be persistent truants who had spent little time in class and had not completed coursework.

The number of teenagers failing to get any GCSEs could rise with the replacement of coursework done at home with “controlled assessment” in the classroom, he added. “If there is a controlled assessment on Friday, February 8 and they do not turn up at school on that day, then they will not have the opportunity to pass,” he said.

Alan Smithers, professor of education at the University of Buckinghamshire, said that many of the young people who left school at 16 with no qualifications had dropped out years earlier. more than 11 per cent of year 11 pupils were persistent absentees.

Raising the education age from 16 to 18 was unlikely to make much difference. “If compulsion were the answer, these young people would be at school already during the compulsory years to age 16.”

Nick Corrigan, of the charity Fairbridge, which supports youngsters not in education, employment or training, said that some young people had so many problems in their personal lives, such as addiction or self-harm, that passing examinations was not a priority for them. “They often find they are ready for exams at a later stage,” he said.

Roy Cook, from Nuneaton, War-wickshire, left school at 16 with no qualifications, and has had jobs in a knitwear factory, as a car paint sprayer, as a builder and, currently, as an electrician. All his work has been obtained through word of mouth. He is convinced that life would have been easier and his earnings higher with formal qualifications.

Now aged 38 and earning around £20,000 a year, he is embarking on his first formal training course, which he hopes will lead to an apprenticeship qualification in two years’ time. “I have had to push hard all my life to work and get work. I will encourage my own children [aged 10 and 12] to get their exams because I don’t want them to have to push as hard as I have,” he said. ]

— Thousands of “coasting” schools which appear to be doing well but have scope for improvement will face annual or even termly inspections.

Christine Gilbert, the head of Ofsted, said that the 45 per cent of schools judged satisfactory or inadequate would receive regular “monitoring visits” between their regular full three-yearly inspections. However, the best schools would face fewer inspections, with a visit every six years, rather than the current three. “We are thinking about tailoring inspections much more,” Ms Gilbert told the National Academies Conference.

The views of pupils and their parents would play a bigger part in Ofsted’s work under the plans.

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