Teachers at two schools in South Yorkshire are refusing to teach two violent pupils who were expelled but re-instated.
They voted on the action - to begin next week - after appeals panels decided the schools had been wrong to exclude the children.
The guidance to appeal panels has been tightened
The action is being taken by members of the NASUWT teachers' union, which recently won a House of Lords ruling on the issue.
One of the children goes to primary school and the other is a secondary school pupil. The schools have not been named.
The cases were highlighted at the NASUWT's annual conference in Bournemouth by Sheffield teacher David Ward.
He told delegates the primary school pupil had attacked four teachers.
"This child - having kicked, bitten and spat at teachers - comes with his own risk assessment, which says he must be treated with tender, loving care," he said.
The secondary school pupil he said had a "record as long as your arm" and had attacked pupils and teachers.
In both cases the schools have been told by independent appeals panels to take the children back.
In a speech with drew loud applause, David Ward said the rights of violent children were being placed above the rights of teachers to teach and other children to learn.
The NASUWT wants to see the appeals panels abolished.
On the increase
Delegates reported what they said was a rising number of attacks on teachers.
Mike Wilson, from Nottingham, said he had been a victim of an attack which had left him with broken ribs.
A survey in his area had painted a picture of teachers subjected to kicking, biting, pinching as well as verbal abuse.
"One had a chair thrown at them across a classroom and was also pushed over. There was no punishment," he said.
Delegates said there was under-reporting of the problem by head teachers, sometimes because they did not want the school to get a bad name.
Les Kennedy, a member of the union's national executive, told the conference the problem was affecting junior and infant schools.
"A five-year-old threw a chair across the class and injured a teacher so badly she was off school for three weeks," she said.
NASUWT general secretary Eamonn O'Kane said union surveys in the north west of England and eastern regions had revealed a "worrying picture of violence and verbal abuse" in schools.
"NASUWT has campaigned for the abolition of independent appeals panels after several bizarre judgements to return excluded pupils to school.
"Teachers are entitled, like any other employee, not to be abused in the course of their work."