Today's league tables reveal that Ermysted's Grammar in Skipton had the county's best results in national tests for 14-year-olds last year, reinforcing its already strong reputation.

Every child who was entered in the tests achieved level five – the expected standard – and the school only just fell short of a 100 per cent record at the higher level.

All schools in the country are also given a "value-added" score, designed to show how far its pupils progress from 11 to 14, and Ermysted's is shown to
have the highest in Yorkshire.

But the school may find it harder to repeat the feat next year when the Government will change the way it measures pupils' progress, taking into account factors that are outside a school's control, like a child's social background.

When the same changes were made to the league tables based on GCSE results earlier this year, high-performing schools struggled to do well.

Ermysted's headteacher, Tom Ashworth, said: "I'm not sure about value-added, I'm not sure what it tells parents."

Mr Ashworth echoed the complaints of headteachers at other high-flying schools that it can be harder to demonstrate they are having an impact on children who are already performing well than it is for schools with pupils who start off at a disadvantage.

He added: "The vast majority of pupils come in with a good level of attainment but having said that they leave at a high level.

"There are high expectations but if you look at grammar schools across the country, not everyone produces the goods."

The success of Ermysted's in today's tables comes just weeks after it was revealed the school had the best A-level results in Yorkshire last year, outperforming all of the region's independent schools.

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