Photo: RNZ / Richard Tindiller
It has written to its members telling them to consider refusing Ministry of Education directions to accept such children unless they are certain they will get enough support.
The federation, which represents hundreds of primary and intermediate school principals, has been complaining for several years about a growing number of students it says are traumatised by their home lives and who pose a danger to other students and to their teachers.
The federation's president, Perry Rush, said schools were not getting the help they needed to safely include violent children in their classrooms.
"There is a national outcry at the moment, a national call for help from principals who are experiencing just being in the vice between the ministry's requirement to have these young people at school and the damage that these young people are causing to the wellbeing of young people and their teachers," he said.