Children from disadvantaged backgrounds need to do more than just attend a good school to boost their educational achievement, a report has claimed.
The report for charity Joseph Rowntree Foundation highlighted how a quarter of poor children in England gain five good GCSEs compared with half of all pupils.
School quality accounted for a fraction of variations in achievement, it said.
Family disadvantage is passed on from one generation to the next in a cycle of underachievement, it added.
The report said that factors such as how children felt about themselves and their learning also needed to be tackled.
'Chavs and posh'
The report, which summarises the findings of eight earlier projects for the charity's education and poverty programme, seeks to understand the well-known correlation between poverty and low educational performance.
Parents who were making a choice between low income and long hours found it hard to give children good life chances, the report added.
It claimed that just 14% of the difference between individual's performance was down to the quality of the school.
Report author Donald Hirsch said: "What this means is that if you simply looked at factors which varied from one school to another - there would not be that much difference in educational performance.
"Looking at children's social background had much more of an impact."
This research did not imply that poorer parents don't care about their children's education
Joseph Rowntree Foundation report
Children were highly aware of their social position and the limitations it placed upon them.
Many had clear stereotypes of "chavs" and "posh" children, the report found.
And children from different backgrounds had different attitudes to their learning and schools, which were developed at an early age.
For example, those in disadvantaged schools complained that they were shouted at by teachers, whereas those in more advantaged schools did not mention this.
The children concluded that those who had been able to develop reading and writing outside school were more confident and had higher self-esteem, the report said.
Mr Hirsch added that if children did not feel confident about their learning they were reluctant to invest effort into it.
What did help was more activities outside school which could help children develop their confidence.
Out-of-school activities should not be just an add-on, the report said, instead they were absolutely central to raising achievement.
The report also found children in advantaged homes not only had more help with their homework but more physical space to do it.
"This research did not imply that poorer parents don't care about their children's education.
"Many parents on low incomes lack the resources that allow them to help out, to provide conducive environments or to access relevant services," it added.
The arrival of extended schools, which will provide homework clubs and help for children and families, offered the opportunity for children from disadvantaged backgrounds to experience some out of school learning that better off children had access to, the report said.
But Mr Hirsch said there was a risk they would reinforce the negative perceptions that some disengaged children already had of school and learning.
Schools minister Lord Adonis said helping children from disadvantaged backgrounds was one of the government's key objectives.
The report's findings chimed with many of the things the government was already doing, he said.
"We will continue to focus on making sure every child can fulfil all aspects of their potential, regardless of their background."