A primary headteacher incensed at the new testing regime has written an emotional letter to parents saying that it “breaks his heart” to give out the Sats results.

Andy Fawkes, head of Linchfield primary, Deeping St James, Lincolnshire, said that his current Year 6 pupils were on course to do better than the children who had taken the test the previous year and is “immensely proud” of them.

He says his school’s initial results indicated they had “plummeted” on last year, with 51 per cent not reaching the expected standard in reading, writing and maths - not far off the national average of 47 per cent failing to come up to the mark.

He tells parents that he is “devastated” by the results and “immensely angry” on behalf of his pupils.

“I know all of your children,” he writes. “They are inquisitive and curious. They have many interests and talents ranging from music to sports. They have acquired many life skills which will stand them in good stead for the future.”

He concludes: “Each one of them is ‘secondary ready’ despite what a poorly devised assessment system says’.”

Parent Jo Stark, whose son Josh is in Year 6, said: “I am pleased he sent the letter to parents. It is very informative and encouraging. The children have worked very hard and the Sats aren’t really a great means of showing how children have progressed.”