The former schools minister Nick Gibb has urged the new ministerial team at the Department for Education to avoid “siren voices” lobbying to abolish GCSEs, saying such a move would be “dismal and unambitious”.

Mr Gibb, who was ousted from his post in last week’s cabinet reshuffle, has said it will be a tragedy if the government stopped pushing forward its planned reform of teacher training.

Writing for the Conservative Home website, he also claims that the creation of new free schools will be just as important as the £3bn extra funding to ensure children in the most deprived areas catch-up from the impact of the Covid pandemic.

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Mr Gibb’s article is strongly critical of what he calls a “progressive ideology” in education, which he says has not gone away.

The former minister has been part of government for most of the last decade, after having first been appointed in 2010.

Defending his record in office, he says: “For the first time, a Conservative government systematically challenged the so-called “progressive” approach - an ideology which downgraded the importance of knowledge and academic rigour and which argued that children learn better through projects and through self-discovery (‘finding out’ as the Plowden Report termed it in 1960) than by teacher-led teaching.

“This philosophy decries exams and dismisses the importance of committing knowledge to memory. It is a philosophy which was failing - and in some schools, despite the huge improvements we’ve made, is still failing - generations of children.”

The cancellation of exams because of the Covid pandemic has led to debate about the future of assessments and exams.

On this question, Mr Gibb adds: “I urge my successors to resist the siren voices of those who call for GCSEs to be abolished. Nothing would widen the attainment gap more than such a dismal and unambitious policy.

“For a large minority of people, GCSEs are the last academic qualification they will take. Remove them, and that group lose any valid certification of a broad education. GCSEs also serve to define a demanding curriculum and they help hold schools to account. Remove them and weaker schools will grow weaker still.”

His piece also makes the case for the policy reforms and changes that have been introduced during his time in office, such as the creation of the phonics check and the roll out of the academies and free schools programme.

He said the latter had “unshackled schools from the cloying control of local authority bureaucracies”.

And he praised schools opened through this policy which are “serving the most disadvantaged parts of the country that are delivering a standard of education that rival or exceed the best in the country - state or independent”.

His piece concludes by urging ministers not to abandon the government reforms.

Mr Gibb said: “If I were to give the newly reshuffled team at the DfE one piece of advice it would be this: remember that reform must be a continuous process, the speed can change but momentum must not stop.

‘If we let up . . .the tide will turn’

“If we let up our concentration on standards, on what evidence tells us works; if we stop pushing forward the knowledge-based curriculum or abandon changes to teacher training, the tide will turn.

“It’s hard work, but the progressive ideology has not gone away. It would be a tragedy for future generations if we gave in and settled for an easier life.”