Schools in deprived areas should be given more money to help compensate for the limited educational support available to pupils at home, the study by the London School of Economics' centre for analysis of social exclusion found.
A more equal society? said that since the 1980s, the attainment of pupils from well-off families has increased faster than that of pupils from disadvantaged backgrounds.
Under Labour, it said, progress in primaries that serve poor areas has increased faster than the average, and targeted initiatives such as Excellence in Cities have had a positive impact. But it also reported that the picture in secondaries is "mixed", and that participation in higher education is now more dependent on family background than it was before 1997.
Funding increases for schools "appear to be insufficient" and "a great deal more needs to be done" to tackle inequality, it said.
The call for more money for schools in deprived areas is a direct challenge to the Government's plans to guarantee all schools a minimum increase in funding per pupil.
The Audit Commission, the public spending watchdog, and MPs on the education select committee have warned that the guarantee will prevent increases in funding from being directed to areas where they are most needed.
The study also called for:
* a higher level of welfare support for low-income families to help them to overcome their disadvantages, including health problems and a lack of resources in their homes that can hamper pupils' progress.
* a higher level of educational support for disadvantaged pupils.
* higher staffing levels for schools with very disadvantaged intakes.
The study, funded by the Joseph Rowntree Foundation and the Economic and Social Research Council, assesses the Government's attempts to tackle poverty - among people ranging from children to pensioners - since it was elected in 1997.
The Government is "on track" to hit its target of reducing the number of children living in poverty by a quarter between 1998-9 and 2004-5, but UK child-poverty rates are still above the European Union average, it said.
A More Equal Society? New Labour, poverty, inequality and exclusion, edited by John Hills and Kitty Stewart, is available from Marston Book Services, price pound;19.99. Telephone: 01235 465500