If the grammar school-baiting Ed Balls succeeds in his struggle against selection in education, the class war will have been won – at least in part – on the playing fields of Eton.

The schools secretary has revealed that as a child he lived briefly at the Berkshire public school when his father, Michael, taught there in the early 1970s.

Balls’s closet Eton past is likely to surprise many on the Labour left who revel in taunting David Cameron, the Tory leader, and Boris Johnson, the London mayor, for being educated at the school.

“While my father was at the University of East Anglia he did a swap with a teacher at Eton,” said Balls, 41, as he queued for fish and chips at an event he was attending with his father in Norfolk on Friday. “For one term a master went to Norwich and we went to Eton – I didn’t go to the school itself but another local [primary] one just for that term.”

Balls angered grammar school parents last week by blaming selective education for making those who fail their 11-plus feel like failures. He announced extra funding for secondary moderns to help them compete with grammars for the best teachers.

“Let me make it clear, I don’t like selection,” he said.

Michael Balls, a scientist who gained a high reputation for his work in reducing the need for animal experiments in medicine, is now emeritus professor of biology at Nottingham University. He was a lecturer at East Anglia in the early 1970s.

He was fiercely opposed to grammar schools, organising the campaign against the 11-plus in Norfolk. This did not stop him later educating his son privately at Nottingham high school.

Balls, despite his privileged education, has gained a reputation for trying to close off attempts by the middle classes to dominate the best schools in the state system. Faith schools have been named and shamed for “covert selection” by discreetly screening out deprived families. Balls has been accused of conducting a witch-hunt against religiously controlled education.

He has now switched his attention to grammar schools, pointing out that secondary moderns have six times more children from deprived families than their grammar school neighbours. Next month, Balls will publish a new strategy to help secondary moderns.

The schools secretary has been more reticent about independent schools, however.

Eton does have other links with Labour. Its provost, Sir Eric Anderson, was housemaster to Tony Blair at Fettes college in Edinburgh and later became chairman of the Heritage Lottery Fund and an informal confidant of Blair.

The Ballses are well established in the Norfolk county set and the schools secretary holds a season ticket at Norwich City football club along with Charles Clarke and Ian Gibson, the local Labour MPs.

Gibson said he had vivid memories of the consternation caused at East Anglia by Balls Sr’s Eton attachment.

“I tried to stop Mike Balls doing this sabbatical when I was on the university senate, although in the end it had to be a matter of personal choice,” said Gibson. “I said, ‘What’s going on here? Here’s the man who fought the 11-plus bloody well going to Eton’.”

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