School scores annulled over errors
Twenty-five primary schools had national curriculum test results wiped out this year due to cheating or mistakes in administering the papers, official figures show.
In some cases, schools saw both their reading and maths scores annulled because of "maladministration".
The disclosure comes as new figures show that hundreds of primary schools in England are failing to give their pupils a decent education in reading, writing and arithmetic.
The statistics, published in annual league tables, also reveal a wide variation in the quality of primary education across the country, with a third of schools in one area of the country considered below par.
The new rankings show how more than 15,000 primary schools performed in national curriculum tests - known as Sats - which are taken by 11-year-olds.
Under the Government's tougher standards, for the first time schools are judged on the number of children achieving at least a Level 4 - the standard expected of the age group - in reading and writing as separate subjects, as well as maths.
They must ensure that at least 60% of pupils reach this level in all three subjects and meet national averages in pupil progress to be considered above the floor.
Schools that fail to meet the target are considered under-performing and face being taken over and turned into academies.
In previous years, they were rated on reading and writing combined to form an overall English result, and maths, as well as progress.
In total, 767 schools have fallen below the Government's new tougher floor standards for primaries.
An analysis of the figures shows that 25 primaries - including 17 with at least 30 pupils sitting the tests - saw none of their pupils score at least a Level 4 in reading, writing and maths combined.
Of these, 13 scored 0% for maths, a further 11 had no results for both the reading and maths tests and one registered no reading results.
Among those scoring 0% overall after having its maths results annulled was Newton Farm Nursery, Infant and Junior School in Harrow, which has been one of the top schools in the country, topping rankings based on schools' average point scores in the tests, for the last two years.
A note in a newsletter, published on Newton Farm's website said that the school's governing body had commissioned an independent investigation into this year's tests and found that "a handful of papers had been altered" and taken action accordingly.
The DfE said all 25 primaries had their results annulled due to "maladministration" - which ranges from schools opening papers early to cheating by pupils or teachers.
A Government analysis of the new performance data shows that this year, in 94 primary schools every child achieved a "good" Level 4 in the reading and maths tests, as well as scoring at least a Level 4 in writing, which is assessed by teachers. This means they are considered ready for secondary school.
This year's top school overall, based on those with 30 or more pupils taking the tests, was Fox Primary School in Kensington and Chelsea, west London. It gained the highest average points score at 34.
A number of other, smaller primaries, had higher average points scores. These were St Oswald's CofE Aided Primary School in Chester CH1 which has eight pupils and a score of 35.4, Litton CofE Primary School in Buxton with 35.0 (six pupils), St Joseph's Roman Catholic Primary School in Clitheroe with 34.9 (seven pupils), Skelton School in Penrith with 34.2 (17 pupils) and Lowbrook Academy in Maidenhead with 34.1 (29 pupils).
But there differences in performance around country.
In Poole, 33% of primaries are considered failing by the Government's benchmarks. In a further 17 local authorities at least one in 10 schools did not meet the floor targets.
It comes the day after Ofsted chief inspector Sir Michael Wilshaw warned that England is still a nation divided into "lucky and unlucky children".
In his second annual report, Sir Michael said that living in poverty is no longer an automatic predictor of failure at school and that many "lucky" children live in disadvantaged inner city areas and attend good schools. Other "unlucky" children are poor youngsters living in reasonably rich areas in places like the Home Counties.
The Department for Education said the data suggested schools are improving and that last year 834 primaries would have fallen below the new standards.
A spokesman said: "Schools with a long history of under-performance, and who are not stepping up to the mark, will be taken over by an academy sponsor. The expertise and strong leadership provided by sponsors is the best way to turn around weak schools and give pupils there the best chance of a first-class education."