Examiners may have been pleased with the command of language displayed by the 11-year-olds who enlivened their answers in this year's English national curriculum tests with expressions such as “nerve-racking” and “spine-chilling”.

That was before they read the papers of hundreds of other candidates who conveyed similar emotions, although not always so eloquently.

The children were asked in one paper to write about their memories of Year 6, their final year at primary school. Many said that it had been spoiled by one thing: their national curriculum tests, also known as SATs.

“I hate SATs week!” was one candidate's succinct response. Another wrote: “I was worrying so much through the register that I didn't even answer my name. It was horrible.”

“Everyone was dreading SATs, including me. We worked ever so hard and I was fed up by the end of the week and could not look at a test ever again,” said a third.

“It was the most nerve-racking thing I had ever come across,” one complained. Another wrote: “This year has been a hard one because of the spine-chilling SATs.”

Mick Brookes, general secretary of the National Association of Head Teachers, which collected the answers from schools, said the answers suggested that the SATs were putting children off learning and narrowing their focus of study.

The tests are marked externally and used to rank schools according to performance in the league tables. The union wants to replace them with internal assessments. Mr Brookes said: “The sooner we move to a teacher assessment approach, similar to that at Key Stage 1, when children are 7, with appropriate moderation and accreditation, with sample testing for purposes of national statistics, the better for all.”

A recent report from the House of Commons schools select committee said: “School accountability should be separated from [the] system of pupil testing, and we recommend that the government consult widely on methods of assuring accountability which do not impact on the right of children to a balanced education.”

Ed Balls, the Schools Secretary, insists that testing at 11 and 14 must contain an element of external validation, but he has conceded that this might take the form of internal marking that is then validated by outside markers. “Nothing is being ruled out or in,” he has said.

The Government is already trying a new system of testing, in which children sit less formal papers twice a year. Children are entered only when their teachers believe that they are capable of passing, similar to the approach taken in grade tests for music exams.

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