Two of England’s biggest classroom unions are considering industrial action to block the tests next year.
Under plans, teachers would refuse to prepare or invigilate for exams taken by some 1.2 million primary school children.
The move would throw Sats into chaos and make it almost impossible for the tests to proceed.
Joint action is being proposed by the National Union of Teachers and the National Association of Head Teachers amid claims the exams destroy children’s education.
They say schools are being forced to “teach to the test” to boost their position in Government league tables.
Many pupils spend hours sitting practice papers and brushing up on exam techniques, severely restricting the amount of time they spend doing PE, art, drama, history and geography, it is claimed.
Mick Brookes, general secretary of the NAHT, which represents 28,000 heads and deputies, said: “We feel it is unconscionable that we should simply stand by and allow the educational experience of children to be blighted and for colleagues to be humiliated and demeaned on an annual basis by the publication of league tables.”
Ministers have already axed Sats for 14-year-olds.
The tests - in English, mathematics and science - were abolished following the fiasco surrounding the marking of last year’s exams. Thousands of children were forced to wait up to six months for results following blunders by a private contractor.
But 11-year-olds are still subjected to tests in their final year of primary school. Children also assessed by teachers in the classroom at the age of seven.
Next month, the NUT and NAHT will call at their annual conferences for “joint action” to stop the exams beyond 2009.
A resolution - which is almost certain to win unanimous support - will culminate in a ballot for industrial action unless the Government agrees to abolish tests.
Ed Balls, the Schools Secretary, has already proposed reforms of the existing system - replacing end-of-year exams with a series of shorter, less pressurised tests pupils sit when they are ready. --By Graeme Paton, Education Editor Last Updated: 2:35PM GMT 25 Mar 2009
But teachers insist they will fail to address fundamental concerns.
Christine Blower, acting NUT general secretary, said: “Primary schools’ patience in enduring the damage caused by the tests has been stretched to the limit and beyond. It is particularly unfair and unjust that the Government wants primary schools to continue with the very tests that it has decided to drop in secondary schools.
“Our deadline for the end of Sats of 2010 is reasonable and our alternative is one which will enhance teaching and learning. Above all else, the Government needs to understand that this year’s tests will be the last.”