By Alex Stevenson Follow @alex__stevenson
The coalition is expanding its pupil premium, as part of a bid to narrow educational attainment between the richest and poorest in society.
Schools minister Sarah Teather is expected to confirm an increase in the amount of funding each school can claim for each disadvantaged child later.
At present schools can receive £488 for each pupil who is eligible for free school meals, under a measure introduced by the coalition government last year.
The focus on education was a key part of the Liberal Democrats' general election manifesto.
Ms Teather is set to announce that all those eligible for free school meals within the last six months will also be covered by the premium, benefiting a further 500,000 pupils.
"In a fair society, it's the government's responsibility to close the gulf in achievement, where the poorest children are less likely to leave school with five good GCSEs than their less-deprived classmates," Ms Teather said.
"[The pupil premium] will help schools tackle the inequalities that have been a part of our state system for far too long. Thousands of children will finally be getting the extra support they need to succeed."
The coalition plans to slowly increase the yearly funding for the pupil premium during its time in government, from the £625 million it is spending this year to £2.5 billion by the 2014/15 financial year.
Shadow education secretary Stephen Twigg said the figures were undermined by the coalition's broader spending cuts to education, which independent analysts claim are the biggest since the 1950s.
"My real concern with the pupil premium is there is no process of accountability," he said.
"Some schools will no doubt use the money effectively to improve attainment for children from poorer backgrounds.
"But because [education secretary] Michael Gove will not give guidance to headteachers on ways to do that, nor monitor how the money is being used, we have no way of knowing what the pupil premium is being spent on.
"Both parents and taxpayers rightly want reassurance that public money is being used wisely."