Ontario's elementary teachers will start a work-to-rule campaign on Tuesday that they say will not affect students.
The Elementary Teachers' Federation of Ontario says their action will target ministry and school board administrative tasks.
Three of the four major teachers' unions, including the elementary teachers, are taking steps toward potential strikes.
Elementary teachers will be in a legal strike position on Nov. 25, and high school teachers will be in a legal strike position next week.
Catholic teachers have voted 97 per cent in favour of a strike but aren't yet in a legal strike position, while talks between the government and French teachers continue.
Negotiations between the province and the education unions started on tense terms a few months ago amid government moves to increase class sizes, and recent legislation to cap wage increases for public sector workers has further angered teachers.
