"We are focusing very specifically on attendance and supervision, which are two areas that principals have identified as areas of concern for student safety," said Broten.
The Ontario Secondary School Teachers' Federation announced teachers at 20 boards across the province, including Toronto, Ottawa, Niagara and Thunder Bay, would begin a series of "strike actions" Monday after talks with the province collapsed during the weekend.
Broten said she was willing to keep talking but the union walked away from the table.
OSSTF president Ken Coran did not return calls Monday seeking comment, but a bulletin on the union's website says that among other actions, teachers will not attend staff meetings, communicate with parents outside school hours or fill in for absent colleagues.
The protests against legislation that freezes wages of most teachers for two years appear designed to disrupt administration of schools but not classrooms or extra curricular activities. But principals are concerned students are caught in the middle.
"The only way to ensure that students are safe is to have an adequate number of teachers and trained adults supervising in the school every day," said Ken Arnott, president of the Ontario Principals' Council.
"If this supervision is withdrawn, or if on-calls for absent teachers are not covered, schools will not be safe places for learning."
Broten echoed the principals' concerns and said the government is trying to understand how the job actions are impacting students.
"We’re very closely monitoring it, and if we need to respond we will."
Teachers unions still have until Dec. 31 to bargain new contract agreements with local school boards based on the province's earlier deal with Catholic teachers, which does allow younger teachers to still move up the salary grid.
School boards would have few options beyond locking teachers out if they feel student safety is at risk, but Brotten said the province has more powers to stop specific actions under the teachers' wage freeze bill, which the Liberals called the Putting Students First Act.
"We have different tools that are more finessed," she said.
"It’s not about lockout. It’s about: 'you can’t do this, you can do this, you can’t do this.' It’s more specific."
The OSSTF represents 60,000 members and is among three unions protesting the Liberal government's wage freeze legislation, which also cuts benefits such as the right to bank sick days and cash them out on retirement.
Some teachers who aren't necessarily in a strike position have already withdrawn from voluntary activities such as coaching and parent-teacher meetings.
The Elementary Teachers' Federation of Ontario has advised its 76,000 members to write only the bare minimum on report cards to protest the legislation.
Four unions are taking the government to court, arguing the wage freeze law _ passed with the help of the Progressive Conservatives _ is unconstitutional and violates collective bargaining rights. It also allows the government to impose its own agreement if it doesn't like what the unions and school boards negotiate together.
The Liberals are also hoping to get almost half-a-million workers in the broader public sector to accept a two-year wage freeze to help eliminate a $14.4-billion deficit by 2017-18.
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