Russell Hobby, general secretary of the NAHT heads' union, said today that there was "no reason" to believe that in the long term schools could not reach the ambitious new standards called for today by the think tank Centre Forum.
The organisation, which is chaired by former schools minister David Laws, has today published a report urging the government to bring in tough new targets for schools' GCSE and key stage 2 results, in a bid to raise England's education system to a "world class standard".
The report, by Centre Forum and Education Data Lab, said that 75 per cent of children should, by 2030, achieve at least 50 points in the new "Attainment 8" measure, which will be introduced for all schools later this year.
This would mean scoring on average a grade 5 – the equivalent of a high C or low B in current GCSEs – in eight subjects. Estimates suggest that just 35 per cent of pupils performed at the equivalent level in 2014, it said.
The report called for a "sensible goal" of 85 per cent of 11-year-olds achieving the equivalent of a level 4b in reading, writing and maths by 2025, compared with just 57 per cent today.
It called for a new target of eliminating the progress gap between pupils from deprived backgrounds and other pupils by 2030.
"These would be bold ambitions," Mr Laws wrote in an introduction to the report. "We want to initiate an informed debate over whether these are the right goals for our country."
Mr Laws said today that attainment had risen and the "disadvantage gap" had fallen over the last decade, but that there was "no cause for complacency".
"Almost 45 per cent of children continue to fail to reach national benchmark standards, which are already lower than the standards reached in the best performing countries," he said. "This will be brought sharply into focus when the new GCSEs are introduced in 2017, with a more challenging standard for a 'good pass'."
He warned that when new GCSEs, which will be graded 9 to 1 rather than A* to G, are introduced from 2017, "we may well see a fall of over 20 [percentage points] in the proportion of English children regarded as reaching the new 'good pass' standard of a grade 5."
Mr Hobby told TES that school performance was improving, adding: "I think that given enough time and support, there’s no reason that those targets shouldn’t be achievable."
However, he warned that setting targets alone was not enough to improve performance. "It's very easy to come up with targets and give them to people, but giving real strategies for how to transform a whole system is much harder," he said.
"The hard part is providing the resources and the evidence base that will help people to get there."
Ofsted's chief inspector Sir Michael Wilshaw is expected to respond to the proposals in a speech at an event organised by the thinktank tomorrow.
The Centre Forum report said that a "comparable outcomes" system used by exams watchdog Ofqual, which avoids "grade inflation" by keeping grades relatively constant from year to year, would have to be used in a different way than at present in order to allow schools to reach these standards.
"The implementation of this process has been criticised even under the unreformed GCSE system for depressing results at Key Stage 4 and preventing pupils from being awarded higher grades than would have been the case in previous years," it said.
"However a new benchmark test will help inform Ofqual's judgements in the future. It is important that the comparable outcomes approach does not suppress real improvement in performance."
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