The Elementary Teachers' Federation of Ontario announced the work-to-rule action last month and although schools have remained open and extracurricular activities and field trips have continued, teachers have not been performing certain administrative duties.
The union says it will further withdraw from Ministry of Education meetings, workshops and mandated meetings with principals.
The union said in a release that the action is administrative in nature and would have "minimal impact on students" with aims to "prod" the government.
Education Minister Liz Sandals has said she was disappointed with the decision for work-to-rule action, but was "encouraged" that students would remain in the classrooms.
Federation President Sam Hammond said in a statement that strike action is increasing due to the "obstinacy" of the government and the Ontario Public School Board Association, adding it was "time the government and OPSBA stopped playing games."
The federation says the school boards have made demands that would allow for increases in class size, have teachers' preparation time directed by others and compromise their ability to support student learning.
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