PRESSURE to succeed in league tables is leading some schools to narrow the national curriculum and 'move out' pupils who will bring down results, Ofsted chief Amanda Spielman has said.

In her first keynote speech since taking over as the chief inspector of schools in England, Miss Spielman will say the situation in some schools is 'nothing short of a scandal'.

It comes after Darwen Alridge Community Academy (DACA) was said to have moved a large number of children out, something which could have boosted its league table results, academics said.

At the time the data was strongly disputed by academy bosses who said they have ‘never manipulated a league table performance’.

Last month researcher Education Datalab said DACA sent 35 students over two year groups in 2013/14 and 2014/15 to alternative schools, the seventh most in the country.

It's GCSE pass rate could have been 40.3 per cent rather than 56.5 per cent when results were recalculated, placing it second nationally for the size of the impact, the organisation said.

The head of the watchdog used her address to the Association of School and College Leaders' annual conference to announce a major Ofsted investigation into how well schools are using the curriculum to ensure children receive a broad education.

Miss Spielman said: "We know that there are some schools that are narrowing the curriculum, using qualifications inappropriately, and moving out pupils who would drag down results.

"That is nothing short of a scandal.

"Childhood isn't deferrable, young people get one opportunity to learn in school; and we owe it to them to make sure they all get an education that is broad, rich and deep.

"There is more to a good education than league tables.

"Vitally important though a school's examination results are, we must not allow curricula to be driven just by SATs, GCSEs and A-levels."

Last month Brendan Loughran, executive principal, said student numbers have grown since the school opened in 2008 so the suggestion they were moving people off roll was ‘not true’.

He said the data also included students who were on the roll but had not attended the school for a variety of reasons.