Margaret Earnshaw, headteacher of Greetland school in Halifax, invited her staff to sign a petition which says tests are "a symbol of everything that is currently wrong with the education of our children".
After a favourable response from parents who work at the school she intends to ask all parents to support the campaign in the next edition of the school's newsletter.
Her action is part of a campaign organised by John Berry, secretary of the Hertfordshire branch of the National Union of Teachers. He hopes to create "unstoppable momentum" against the tests by the time of the union's annual conference in April.
The NUT leadership this week called on other classroom unions to consider boycotting national primary school tests because they "distort" the curriculum and increase pressure on staff and pupils.
It follows a survey of members which found that nine in 10 would support a ballot to boycott tests, although most would only do so if other unions followed suit.
Mrs Earnshaw told The TES that she was backing the campaign because pressure to meet targets is damaging the school's commitment to providing a broad and balanced curriculum.
"The spontaneity of enthusiastic teachers is being eroded because they are forced to work towards the tests," she said. Last year all pupils at Greetland gained the expected level for key stage 2 science tests. Figures for maths and English were around 90 per cent.
Mrs Earnshaw said that Office for Standards in Education inspections were a better way of assessing a school's overall worth and criticised the Government and press's "obsession with numbers".
She said that Year 6 pupils had complained of being stressed well before the tests actually took place.
A government spokseprson defended the tests: "Our primary strategy has delivered the best-ever results and regular assessment is an important part of that."