New generation of grammar schools to take on 'more pupils from ordinary working families'
Video report by ITV News Political Correspondent Paul Brand
New grammar schools will be "truly open to all" and take on more people from working-class and disadvantaged backgrounds, according to the education secretary.
The government say its plans for a new generation of grammars mean selective schools will "work for everyone".
Justine Greening's comments come as a consultation found that families with incomes below the national average find it harder to access outstanding schools.
But Tory plans for a transformative generation of grammars will increase intake of children from "ordinary working families".
Labour has criticised the government's plans, however, with Jeremy Corbyn tweeting that that they were "divisive".
The government consultation concluded that families not included in traditional measures of poverty, but with below average household incomes, find it more difficult to attain places at top-performing schools.
Children from such backgrounds also perform worse at school than wealthier peers, it found.
Government report classification of "ordinary working families"
Families with no children receiving school meals
But those below median income level
Income of £33,000 for a two-parent family with two teenage children
Or £17,000 for a single parent with one child
But Ms Greening, in a speech on Thursday at St Mary's University in south-west London, is expected to say she wants new grammar schools to "work for everyone".
They will be "truly open for all" and cater more and more for "ordinary working families" - including those from suburbs and coastal areas.
Since the results of its consultation, the government has also launched a further one to better understand how working-class children fare at school.
Ms Greening will say: "This is a Government that believes that ordinary working families shouldn't have to 'make do'.
"We believe they deserve better than that. Because ordinary working families are the backbone of our economy, of our country."
She will add: "And I believe that selection - in new, 21st century state grammar schools - will add to the options available to young people - to truly help make the most of their talents.
"And grammars should not just be for one better off group in society to attend. We want to see more children from disadvantaged families get into grammars - that's vital."
Grammar schools will increasingly support young people "from every background, not the privileged few".
Labour were critical of the plans and urged the Conservatives to scrap the increase in grammars.
Mr Corbyn, who has called for free school meals for all children, believes the government is not properly funding schools.
He tweeted: "If the Tories wanted to help all children, they'd scrap their divisive grammar school plans & properly fund schools."
Meanwhile, Labour's shadow education secretary Angela Rayner said: "The facts are clear, grammar schools will do nothing to help the overwhelming majority of working families across the country.
"The Government's attempt to fiddle the figures to support their discredited and divisive policy does not change the basic reality that for the overwhelming majority, academic selection is a barrier to social mobility, and the Government's plans to return to the days of secondary moderns will only make this worse."