Teachers are mobilising parental support for a big campaign against national tests for children at the ages of 7, 11 and 14.

Mick Brookes, the general secretary of the National Association of Head Teachers (NAHT), put the Government on notice yesterday that it faced “trouble ahead” if it did not listen to teaching professionals and parents who believe that the tests distort children’s education and put them off learning.

Speaking at the union’s annual conference in Liverpool, Mr Brookes refused to rule out a boycott of the tests, which he described as “expensive nonsense”. “If there is still this complete obstinacy we will have to consider our options by November this year,” he said.

Mr Brookes pointed out that there was near-universal opposition to the system of national testing in England. He said that he was gathering support from other unions, from the National Confederation of Parent Teacher Associations and other experts to take on the Government over the issue.

Ministers have plans to replace the tests in 2011 with single-level testing, which is being tried at the moment. Conference delegates gave warning, however, that the new system could result in children taking even more tests than they do now. The pressure on teachers and pupils to do well would remain, they said, as long as results were used to rank schools in league tables. Mr Brookes called for pupils to be measured primarily by internal teacher assessments from next year.

Beverley Hughes, the Children’s Minister, was jeered when she defended the testing regime, saying that parents and the public wanted test results to show how pupils and schools were performing.

Margaret Morrissey, of the National Confederation of Parent Teacher Associations, said she thought that most parents would be satisfied with teacher assessments to tell them how their children were doing.

“When we surveyed our members, it was clear that they did not support Key Stage 1 testing at 7,” she said. “They thought it was too stressful for the children. When the tests were first introduced, we were told the children would never know when they were sitting the tests. But now the children are being coached for them, they are told they must not be off school on the test day and they are thoroughly wound up.”

She added that parents had similar views of Key Stage 2 and 3 tests for children aged 11 and 14.

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