Some high schools serving more deprived communities have benefited the most from the new system to judge their performance in GCSE exams, an EDP analysis has found.

This week's provisional GCSE school league tables were the first to use the Progress 8 score, which aims to measure the average improvement made by pupils since they left primary school.

It replaces the previous 'gold standard' - the percentage of pupils gaining at least five GCSEs at A* to C, including English and maths.

This week's data showed how schools performed on Progress 8 this summer, and, separately, the percentage of pupils at each school who gained at least a C in both English and maths.

A comparison of where Norfolk schools stand when ranked on these two different measures has shown that seven jumped by 15 places or more when the new Progress 8 system was used.

All serve less prosperous communities, a factor which is often correlated with lower exam results, and therefore put them at a disadvantage under the old league table system.

St Clement's High, in Terrington St Clements in west Norfolk, jumped 34 places, while Cliff Park Ormiston Academy in Gorleston rose 28 places, and Great Yarmouth High, which was bottom of the table on the English and maths measure, went up 24 places.

Some of the league table positions are not exact, because the margins of error for the Progress 8 scores for some schools overlap.

In contrast, four high schools that performed well on the number of pupils gaining at least a grade C in English and maths saw their positions in the Norfolk league table drop by at least 15 places when Progress 8 was used.

Wymondham High Academy experienced the biggest drop, falling 30 places.

A total of 23 schools saw their league table positions remain broadly similar under the two rankings, rising or falling by less than five places.

According to the government data, King's Lynn Academy was one of five schools in our region that fell below the government's minimum floor standard.

However, principal Craig Morrison said: 'The results stated are non-validated results and do not include several grades that cannot be counted, due to exam board error. The eventual figure will be above the floor target when final outcomes are released in January.'

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