The NSW Teachers Federation will campaign to remove scripture from NSW public schools after criticising "antiquated" policy that leaves thousands of students unable to do formal school activities if they opt out of scripture classes.

Special religious education (SRE) is mandatory for 40 minutes per week, and students who opt out are not allowed to do any meaningful activity during that period. Ethics is not offered in high schools as an alternative, as it is in primary schools when trained volunteers are available.

Under the current law, students who opt out of SRE can't participate in academic instruction. Credit:Michele Mossop

In a statement issued on Wednesday, Jack Galvin-Waight, the Federation's SRE and special ethics education delegate, said they will "start a campaign to amend the 1990 Education Act in regards to the removal of mandatory SRE".

The council decision was moved by the Newcastle Teachers Association and voted on by about 300 elected delegates representing about 70,000 NSW public school teachers.