An official evaluation of the first academies has painted a mixed picture of the privately-sponsored schools, warning of significant problems including bullying.
Ministers said they were encouraged by the report from consultants PricewaterhouseCoopers, as it indicated that pupils, parents and teachers were very satisfied with the flagship schools.
But the consultants found a range of problems including significant levels of bullying and impractical classrooms.
The report is the second of five annual studies on academies commissioned by the Government. Ministers have pledged that at least 200 of the schools, which typically cost pound;25 million, will be either open or in the pipeline by 2010.
The new report looked at the first 11 of the 17 academies which have opened since 2002. It noted that only six of these schools had improved GCSE passes, but concluded it was too early to judge the impact on academic attainment.
Instead, the study focused on questionnaire responses from 1,666 pupils, 403 staff and 433 parents at the academies.
These indicated that 87 per cent of parents were satisfied with their children's education.
Academy pupils also appeared positive: 84 per cent said their principal was "really interested in the pupils", a view held by only 64 per cent of students in schools with similar intakes.
The report said that such responses "strongly suggest that the academies have indeed managed to achieve a break in the past experience of underachievement and low aspirations".
However, the report said that bullying appeared to be a significant problem, as it was reported by fourth-fifths of academy pupils.
The report also found:
* tensions in staffrooms between specially-appointed teachers and staff who were moved to the academies from the schools they replaced.
* that three-fifths of the teachers said their workloads were bigger than at previous schools.
* concerns about the way pupils with special educational needs were admitted and taught.
While the academies' futuristic buildings looked impressive, the consultants said that too much emphasis had been placed on creating "a bold statement ... at the expense of some of the more practical requirements of modern teaching and learning", such as providing storage space.
The report said there was no evidence that academies were damaging the results of neighbouring schools, although principals at these schools were concerned about the future.
The Academy Sponsors Trust said it was pleased that 78 per cent of the teachers surveyed felt that the sponsors had a positive impact on the schools.
However, the National Union of Teachers said the report's findings were "disturbing". Steve Sinnott, general secretary, said the positive response from children and teachers to the academies was not significant, as pupils and staff at any new school would be supportive.
The private schools company Global Education Management Systems (Gems) announced this week that it was no longer investing in two academies in Milton Keynes following negative publicity surrounding its management of the nearby private school, Bury Lawn.
Hugh MacPherson, Gems' chief operating officer, insisted the company had not ruled out sponsoring academies elsewhere.
The schools and their backers
The Business academy, Bexley, London: Sir David Garrard, chairman of the Garrard Education Trust.
Greig city academy, Haringey, London: Greig Trust, an educational charity, and the Church of England.
Unity city academy, Middlesbrough: Amey plc, builders.
Capital city academy, Brent, London: Sir Frank Lowe, sports agent.
The City academy, Bristol: John Laycock, a director of Bristol City football club, University of the West of England and Bristol Business West.
The West London academy, Ealing: Alec Reed, chairman of Reed Executive, employment agency.
Manchester academy: United Learning Trust, a Christian charity, and Manchester Science Park.
The King's academy, Middlesbrough: Emmanuel Schools Foundation, a Christian educational trust, founded by Sir Peter Vardy, car dealer.
Djanogly city academy, Nottingham: Sir Harry Djanogly, industrialist.
City of London academy, Southwark, London: Corporation of London.
The Academy at Peckham, Southwark, London: Lord Harris of Peckham, chairman of Carpetright.
Walsall city academy: Mercers' Company, charitable grant-making trust, Thomas Telford Online, educational resources company linked to Thomas Telford school.
The London academy, Barnet: Peter Shalson, chairman of SGI Ltd, a venture capital company.
Mossbourne community academy, Hackney, London: Clive Bourne, life president of Seabourne Group, logistics and distribution company.
Stockley academy, Hillingdon, London: Barry Townsley, chairman of Insinger Townsley, stockbrokers.
Lambeth academy, London: United Learning Trust.
Northampton academy: United Learning Trust.
Forty named academies are also under development and their sponsors include: United Learning Trust (five).
Oasis, a Christian trust.
Church of England (four).
Roman Catholic Church (four).
Rod Aldridge, chairman of Capita plc.
The Society of Merchant Venturers, Bristol-based historical organisation.
David Meller, director of Watford FC, and others.
Roger De Haan, chairman of Saga Holidays.
David Samworth, chairman of Samworth Brothers, food manufacturers.
John Madejski, chairman of Reading Football Club.
Arbib Foundation, charitable trust promoting history and geography of the Thames Valley.
Bob Edmiston, chairman of the IM Group, which includes car importer Daihatsu, and Christian Vision, a charitable company aiming to introduce people to Jesus.