Rona Tutt, National Association of Head Teachers president, will open the association's annual conference in Cardiff with an attack on national tests that "have nothing to do with assessment for learning and everything to do with assessment for performance tables".
She is expected to say: "What dehumanises schools is turning them into exam factories, using assessment for accountability purposes and sidelining professional judgment and commonsense."
Unlike last year, the conference will not discuss a call to boycott the tests. An NAHT feasibility study into possible boycotts carried out in 2003 concluded that the Government's changes to key stage 1 testing should be given a chance and that a boycott of KS2 tests was unlikely to gain sufficient support.
But motions have been tabled calling on the Government to end the culture of testing, to abolish external KS2 and 3 tests and to get rid of league tables..
Gail Larkin, head of Auriol junior, in Ewell, Surrey, said: "We are quite happy doing Sats. Our problem is that the results are in the public domain, published and used to compile league tables."
She had several profoundly deaf pupils who could be disadvantaged in the national tests, unfairly distorting her school's position in the league tables which took no account of the number of pupils with special educational needs.
The Government's suggestion that heads should collect fines from parents for truancy is also expected top come under fire.
Ian Bruce, head of Rosemellin primary, in Camborne, Cornwall, has proposed a motion stating that it is inappropriate for any member of school staff to be asked to carry out such tasks.
"This is a daft idea," he said. "We have an education welfare service that can take people through the courts who can then end up with prison sentences. That is the sensible way to counter truancy.
"We should be left to get on with educating children."
Motions have also been tabled calling for a national school funding formula, criticising the Office for Standards in Education and its new inspection regime, opposing the plan to increase teachers' pension age to 65, and calling for anonymity for teachers who are the subject of allegations of misconduct.