Governors at schools where large numbers of Year 10 and 11 pupils have “disappeared” have come under fire for not holding senior leaders to account.

The criticism from Emma Knights, chief executive of the National Governors Association, follows claims that some pupils are being “managed out” of mainstream secondary schools to boost league table positions.

A report published by Education Datalab in January said that 125 schools would have seen their headline GCSE pass rate fall by at least 5 percentage points if league tables were re-weighted to allocate pupils’ results according to how long they had stayed at a school.

Ms Knights told the Bett Academies show in Birmingham this month that in recent years there had been a big focus on “effective governance”, and not enough on “ethical governance”.

She told the audience that “it’s phenomenally important that we are holding our senior executives to account”, and added that boards should be making sure that unethical behaviour does not take place.

“For example, those schools that have an awful lot of pupils disappearing, for want of a better phrase, in years 10 and 11, what were the boards doing about that?”, she asked.

“You can see from the numbers that that is happening. Why weren’t they asking questions?”

This month, the new Ofsted chief inspector Amanda Spielman announced an investigation into whether schools are trying to game the system.

Speaking to TES, Ms Knights said: “It does make you wonder what these boards are doing. We really scrutinise the data, and you can see if in one year you had 150 [pupils] and in the next you have 120.

“I think what probably happened was some of the schools said it was mobility and the governors accepted that without digging down. You have to keep questioning.

“The research shows the weakest governing bodies are those that accept what the headteacher or CEO says. It highlights the need for triangulation.”

She said that governors tend to volunteer because they want to do what is in the best interests of young people, but warned that the pressures of accountability measures could lead to some becoming complicit in efforts to game the system in ways that were not in the best interests of individual pupils

“Sometimes, because governing bodies listen to their headteachers and CEOs, that stress of performance tables and Ofsted gets transferred to governing boards, where really governing boards are the ones who should have the courage to say ‘is this really in the interest of the young people?’”

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