Rishi Sunak said he wanted to create a “world-class” education system as the Government launched a consultation on a new post-16 qualification – the Advanced British Standard – that would see all pupils study some maths to age 18.

The Prime Minister visited Wren Academy in the north London suburb of Finchley on Thursday, as he stressed the benefits of children studying mathematics for longer.

Mr Sunak, whose maths-to-18 plan is a personal passion project, visited a year one class to help pupils with their arithmetic.

After a week that saw Tory whips frantically counting the number of would-be rebels in the Commons, the Prime Minister had an easier time helping the pupils with their sums.

He was not allowed to let his mind drift too far from Westminster, however.

Visiting an art class later with local MP Mike Freer, the Prime Minister was shown one art student’s “cabinet of curiosities” project.

Asked by one of the pupils if he knew what that was, the Finchley and Golders Green MP quipped: “You work in one.”

Parents, teachers, pupils and employers are being invited to share their views on the design of the new baccalaureate-style qualification which will eventually replace A-levels and T-levels.

It comes after the Mr Sunak announced students in England will typically study five subjects rather than three under the major reforms.

Under the shake-up – which is expected to take a decade to establish – 16 to 19-year-olds would take a larger number of subjects at both “major” and “minor” level.

The consultation on the Advanced British Standard (ABS) – which was announced at the Conservative Party conference in October – has been launched ahead of the Christmas break.

But more detailed plans and proposals for delivery are expected to be set out in a White Paper next year, the Department for Education (DfE) has said.

Mr Sunak said the new qualification would bring together “technical and academic education, increases the amount of time children get in the classroom with great teachers and everybody studies some maths and English – not A-level – up to 18 like every other country”.

“We have got to make sure our education system is world class and our children are being prepared for the jobs of the future.”

But Geoff Barton, general secretary of the Association of School and College Leaders (ASCL), said: “We currently have a severe and deepening funding and teacher shortage crisis in education, and the Government is preoccupied with introducing a new qualification which would take a decade to develop and will probably not happen at all.

“It is difficult to imagine a more pointless waste of energy and time.”

He added: “This is truly a form of headless chicken policymaking.”