The Elementary Teachers' Federation of Ontario (ETFO), which represents some 76,000 teachers and has just been through eight months of unsuccessful negotiations with the province, announced its job action plans on Friday afternoon.
"This strike action is incremental in nature," said ETFO president Sam Hammond. He added that it would continue in this manner until certain bargaining demands from the province are withdrawn or until the union determines further actions are required.
What are the issues?
The Ontario Public School Boards Association (OPSBA), which bargains with teachers, says staffing and workload provisions have not kept pace with changes in the classroom.
OPSBA says on its website that the collective agreement with teachers must "address declining enrolment, equity and inclusion [and] application of technology."
But the union says the demands tabled by OPSBA and the province include provisions that could increase the number of students in classrooms, direct how teachers spend their preparation time and rescind "fair and transparent" hiring practices.
"OPSBA wants the ability to determine how teachers teach," said Hammond in an earlier statement.
What are teachers still doing?
According to a bulletin, which was circulated by the union and obtained by CBC News on May 8, ETFO members will continue to teach, take attendance and "provide extra help" to students.
They will also maintain contact with parents "during the instructional day" and provide school administrators with student marks for the June report card.
Participation in extra curricular activities and field trips will continue for now.
What aren't teachers doing?
However, teachers will not fill out comments on those report cards, according to the same bulletin.
Teachers will also not attend staff, divisional or ministry of education meetings. They will not conduct any reading, writing or math assessments — unless the teacher deems them necessary to report on student progress.
Teachers will not participate in ministry webinars, activities or professional development workshops.
The union says its members will also abstain from any activity connected to the province's Education Quality and Accountability Office, which conducts standardized tests in key subjects to students in Grades 3, 6, and 9.
The bulletin describes these efforts as "phase one" of the union's work-to-rule plan, but Hammond would not say what subsequent phases might look like, or when they might roll out.
"We don't want the other phases to roll out," he told reporters on Friday.
"We have not set a timeline for any of those things."