An in-depth investigation into the homelife of almost 5,000 pupils from the age of four provides vital new evidence that social class is a crucial factor in determining whether a child does well or badly at school.
The study - the first to track performance back to reception age pupils - highlights the daunting task facing schools in the most deprived parts of the country as they struggle to hit ambitious government education targets.
Its findings suggest that ministers cannot simply tell schools they must do better - but that poor social conditions must be tackled before there will be a rise in pupil performance.
The research is based on a study of reception and key stage 2 pupils in the London borough of Ealing, tracing them back to their home postal code districts and census data.
It confirms that children from the best backgrounds not only perform better but migrate to the most successful schools. This means that the most needy pupils - those on free school meals - tend to end up in the worst schools.
Researcher Ian McCallum said: "If the Government is to reward good teachers and say that success at school is related to the quality of teaching, it must take account of the quality of the support provided by parents.
"If a school has a bad reputation and is criticised, those parents who are able to provide support and who have the incentive will do their utmost to get their children into a school with a better reputation."
The research, commissioned by Labour-controlled Ealing council, fuels the debate over the relationship between poverty and pupil performance.
It shows that reception-aged pupils from the lowest social groups consistently produced the worst results in baseline assessment tests for reading, writing, speaking and maths.
Almost a third who scored only 0-3, out of a possible 12, were on free school meals compared to only 9 per cent who achieved the top grades of 8-12.
At key stage 2, 54 per cent of pupils scoring the lowest levels in English were eligible for free school meals, but only 14 per cent of those who achieved level 5 and above. Almost half the pupils scoring level five-plus had parents in professional, managerial and technical jobs.
The Prime Minister has made clear his belief that education has a key role to play in regenerating rundown estates. The Pounds 800 million New Deal for Communities announced last week explicitly links improvements in social conditions to improvements in educational performance.
Alongside 17 "pathfinder" projects, 18 cross-department action groups will be set up. Education and employment ministers will sit on 14 of them and chair three - jobs, skills and Schools Plus.
Schools Plus will be led by Estelle Morris, the standards minister, and identify ways of reducing educational failure and use schools as a focus for community services and adult education.
The initiative will analyse the success of schemes such as breakfast and homework clubs, mentoring and involving parents.