I don’t agree with scoring PMQs as if it were a game, but that was 5-1 to Jeremy Corbyn. He spotted that the Government’s attempt to reallocate schools funding would be a breach of the Conservative manifesto – another one, after last week’s U-turn on an increase in National Insurance contributions for the self-employed.

Corbyn quoted the manifesto: “Under a future Conservative government, the amount of money following your child into school will be protected.” That badly drafted sentence means that no school should have funding per pupil cut in the review being carried out by Justine Greening, the Education Secretary, who looked most uncomfortable a few places from the Prime Minister on the Government front bench.

Theresa May had no answer to Corbyn’s question, except to say that the consultation on schools funding ended today and the Department for Education would respond in due course. She claimed that her government was addressing a question that the Labour government had ignored for 13 years. That is a feeble argument, given that there are many younger MPs in the House who think that a Labour government is an ancient myth.

But there was a reason why Labour avoided interfering in the funding formula for schools, which is that any changes create winners and losers, and losers always make more noise than winners. Since Tory MPs assumed that the review would shift money from schools in poor areas to (their) richer places, the anger of those who have discovered that they might lose out after all is enough to force a government U-turn.

Jeremy Corbyn confronts Theresa May about breaking manifesto pledge over education funding

The review is unlikely to happen now, not because Corbyn “won” PMQs today, but because Tory MPs are threatening to rebel against it. Yet the Labour leader managed to press his advantage home and to make it count. This does not always happen, but his weakness became his strength today. May launched a personal tirade on the Labour front bench (Diane Abbott and Shami Chakrabarti) for sending their children to private schools, then said that Corbyn himself had sent his son to a grammar school – something he opposed so strongly that he split up with his wife over it – and said that because Corbyn himself went to a grammar school he was guilty of hypocrisy. It was a disgraceful performance, the worst since Michael Howard, who sent his son to Eton, criticised Tony Blair, who sent his children to state schools, for having been educated at a private school.

Fortunately for Corbyn, he does not think quickly on his feet. Instead of trying to think of a clever reply, he simply ignored the Prime Minister’s personal abuse. This was absolutely the right decision, making May look petty.

She had an effectively prepared putdown for her final answer, but it had nothing to do with schools. And it was rather obviously prepared, because she paused, took a piece of paper out of her folder, to Labour “oohs”, and started to quote from Corbyn’s video produced to try to calm the tension between his deputy, Tom Watson, and his trade union godfather, Len McCluskey.

Corbyn posts unity video after claims of 'hard left takeover'

In the video, Corbyn had urged his members to “put the party first” – so May deployed Liz Kendall’s rhetoric that had been used against Andy Burnham in the Labour leadership election: “Labour puts the party first; we put the country first.”