A government scheme to improve secondary results by pairing good schools with poor ones is backfiring as headteachers denounce it as offensive.
Heads of schools some of which have good inspection reports are enraged that they have been labelled as underperforming and singled out for special help from more "successful" colleagues. They are then told to raise their GCSE and key stage 3 targets in return for a pound;20,000 budget boost.
Under the two-year scheme, launched with no publicity in January, ministers are trying to match successful comprehensives with those that do poorly under a value-added analysis of pupils' results for the Government.
Yet none of these "underperforming" schools is categorised by inspectors as failing. Some successful schools also have misgivings about getting involved with the project.
David Hart, general secretary of the National Association of Head Teachers, this week warned that the School Performance Collaboratives scheme risked alienating headteachers as much as the notorious "bog standard comprehensive" jibe from the former Number 10 spin doctor Alastair Campbell.
Encouraging heads to collaborate or act as "critical friends" of colleagues in other schools is one of Labour's key tactics in driving improvement.
Ministers will be concerned that the latest scheme could sour relations with school leaders.
None of seven heads spoken to by The TES was impressed with the way the scheme had been launched.
The head of a South-west secondary, identified as underperforming despite a recent positive inspection report, said: "I have no problem that the school's results are under much more scrutiny now.
"But this sort of project does not help us to work together."
The head of another "underperforming" school in Staffordshire said:
"Identifying schools as low-performing and high-performing, on such narrow criteria, is unhelpful. I find it offensive."
The initiative covers 123 schools in four English regions: the North-east, East Anglia, the West Midlands and the South-west.
Value-added calculations, assessing the progress each school's pupils make between key stages 2, 3 and GCSE, have been used to categorise secondaries as either successful or underperforming.
These figures are not the same as those included in the value-added secondary league tables, nor in inspection reports. Yet a Department for Education and Skills briefing paper, circulated to heads and seen by The TES, offers little room for doubt on each school's weaknesses.
It says that those identified as underperforming have "significant numbers of pupils who are failing to achieve the promise they showed on entry".
The designated "underperforming" schools will receive help from their partner schools but have to commit themselves to improving their pupils'
grades and to set themselves significantly higher targets for exam and test results from next year.
The head of a school in Gloucestershire which has been identified as successful said: "This is not a very good basis for partnership."
One local authority adviser said that the Government was right to promote the collaborative approach but had been "naive" or "overenthusiastic" in how it was presented to heads.
John Dunford, general secretary of the Secondary Heads Association, said:
"Collaboration between schools is best done when schools choose who they pair up with. The Government should be building long-term partnerships with schools, not presiding over shotgun marriages."
Mr Hart said: "Any attempt to label schools as underperforming, especially on the basis of value-added data which is viewed sceptically by the profession, has the potential to sour this initiative from day one."
A DFES spokeswoman said: "We have no intention of labelling schools as underperforming, which is why we are not publishing the names of these schools.
"This is about recognising areas of good practice and encouraging schools to share information with each other."