Theresa May is facing a new cross-party campaign to derail her flagship education-reform programme to expand the number of grammar schools in England.
Conservative former education secretary Nicky Morgan is opposing the plan together with Nick Clegg, the Liberal Democrat former deputy prime minister, and Labour ex-shadow education minister Lucy Powell.
In a jointly written article in The Observer, the three politicians argue that creating new grammar schools will do nothing to promote social mobility, and insist that there is no room for more division or political ideology in the education system.
"We must rise to the challenge with a new national mission to boost education and social mobility for all," they write.
"That's why we are putting aside what we disagree on, to come together and to build a cross-party consensus in favour of what works for our children – not what sounds good to politicians."
No silver bullet
In their article, Ms Morgan, Mr Clegg and Ms Powell say that an "endless debate" about more selection in the education system risked squeezing out positive developments that were taking place elsewhere.
"Those championing selection as the silver bullet for tackling social mobility, or as the panacea for creating good new school places, are misguided," they said. "All the evidence is clear that grammar schools damage social mobility.
"While they can boost attainment for the already gifted, they do nothing for the majority of children who do not attend them. Indeed, in highly selective areas, children not in grammars do worse than their peers in non-selective areas.
"In a time when resources are so limited and many other educational reforms are still in their infancy or yet to be proved – from university technical colleges and new T-levels to the expansion of free childcare and hundreds of new free schools – now is not the time for more division or political ideology in education."
Other influential Conservatives, including the chairman of the Commons Education Select Committee, Neil Carmichael, have also voiced opposition to the plan. Earlier this month, the new Ofsted chief inspector, Amanda Spielman, said that grammar schools sent "a difficult message" about social mobility: "It’s clear that not very many disadvantaged children get to go to grammar school, though they tend to do very well when they get there.”
Her predecessor at Ofsted, Sir Michael Wilshaw, has also expressed his opposition to Ms May's grammar-school proposals.
With a working majority of just 17, Ms May's vulnerability to intra-party revolts was underlined last week, when chancellor Philip Hammond was forced to back down over his Budget reforms to National Insurance, following a backlash from the backbenches.
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