Fewer than one in 10 teachers think the Government's school reforms will improve the education of disadvantaged pupils, new research has found.
They are also sceptical about the chances of specific policies such as free schools and academies helping less privileged children, according to a survey of 2,199 teachers commissioned by the Sutton Trust.
The findings came as the Easter teaching conferences got under way, with angry condemnations of Government policy expected from union activists.
They will reflect the concerns of the wider profession, the survey, carried out by the National Foundation for Educational Research, suggests.
Only 8 per cent of teachers agreed that the overall package of school reforms had "the potential to improve the educational outcomes for less privileged children", it found, with 64 per cent disagreeing.
Two thirds thought free schools would lead to greater social segregation and 59 per cent agreed that already privileged pupils would be the most likely to benefit from their schools being given academy status.
Sir Peter Lampl, chairman of the Sutton Trust, which campaigns for social mobility through education, said the findings were "very serious" for ministers.
Education secretary Michael Gove has said his reforms will help schools become "engines of social mobility", arguing that schools currently widen the gap between the most and least advantaged. But 69 per cent of the teachers surveyed agreed the academies expansion would increase social segregation.
Only 7 per cent agreed free schools would provide a better education for the less privileged and just 8 per cent thought they would "drive up education standards through increased competition".
Sir Peter said: "Teachers are not only knowledgeable about what is likely to work but they are also the key players in implementing Government reforms and the fact that less than 10 per cent think they will improve outcomes for less privileged children is very serious.
"Clearly the Government has a lot of work to do to convince teachers who remain fearful that moves to increase school freedoms will actually widen attainment gaps between poorer pupils and their more privileged peers."
More than half of teachers - 55 per cent - thought that the proposed pupil premium (extra money for schools admitting disadvantaged pupils) needs to be set at around 50 per cent of standard per-pupil funding. The current figure is around 10 per cent.
The survey found teachers were split over whether freedoms given to new academies would free time for them to focus on improving pupil achievement overall, with 27 per cent agreeing they would and 37 per cent disagreeing.
A Department for Education spokesman said: "We are taking radical measures to raise standards, so that children from every background have the chance to succeed. "The whole focus of the recent schools white paper is on narrowing the educational gap."