A generation of children are at risk of being failed by the government if it does not properly address the educational needs caused by lost learning during the Covid pandemic, a social mobility expert has said. The comments came after the unexpected resignation of the government’s schools recovery chief, Sir Kevan Collins, on Wednesday in protest at its watered-down offer of £1.5bn in funding to help schoolchildren in England catch up on lost learning – a tenth of the £15bn he had recommended. In his resignation letter, Collins said the “half-hearted approach risks failing thousands of pupils” and fell “far short” of what was needed to meet the scale of the challenge. He said disadvantaged and vulnerable children would suffer most and the impact was likely to be “particularly severe” in parts of the country where schools were closed for longer, such as the north. Lee Elliot Major, a professor of social mobility at Exeter University, told BBC Radio 4’s Today programme that children in England had lost 110 of 190 classroom days, and about 2 million children did no learning at all during the first lockdown. Describing Collins as “one of the most respected” people in the sector, Major said he would not have taken the decision to step down lightly. “I just hope it’s a wake-up call for government to see this as the beginning of a much bigger, more ambitious programme. “What we do know, and there is a lot of evidence around this, is that extra teaching for children will have huge benefits. And remember this is an investment for the future. If we don’t address these issues now, the real fear is that we will fail a whole generation. “This is about a whole generation of children and so my belief is that there is compelling evidence that, if done well, if you extend teaching, then that will help us catch up. I don’t see any other way of doing it.” The Home Office minister Victoria Atkins said the government had not ruled out extending the school day to help children catch up after the pandemic, as she defended what she called the “huge” investment in recovery plans. She told Today: “We are reviewing this recommendation about extending the school day.” Atkins said the education recovery fund was “very much focused on what we can deliver and deliver quickly”, despite Collins citing in his resignation letter that the package of support was “too narrow, too small and will be delivered too slowly”. She said she had not read his statement and disputed that he was alleging those worst affected by the pandemic had been failed by the plans. The minister told Sky News the government was “determined to get [children] back on track” and insisted the £1.4bn announced on Wednesday for tutoring was “a huge amount of money”. But the senior Conservative MP Robert Halfon, who chairs the Commons education select committee, said ministers must “decide their priorities in terms of education”, adding that the Treasury could “find the money from the back of the sofa” if there was the political will. He told Today: “Of course there are funding constraints but the Treasury announced over £16bn extra for defence only last year, we’ve got £800m being spent on a new research agency, £200m being spent on a yacht. “So where there is the political will, the Treasury can find the money from the back of the sofa, and there has to be that political will because we need a long-term plan for education, a proper funding settlement.” He said the damage caused by the pandemic to younger children had been “a disaster” in terms of mental health, attainment, safeguarding and life chances. “We need some radical thinking, some thinking out of the box, a proper long-term plan [for education] and I will keep campaigning for that, and a proper funding settlement so that that plan is properly resourced.”