The Elementary Teachers' Federation of Ontario said 35,000 teachers, including nearly 14,000 in Toronto, hit the picket lines in what some called "Super Tuesday" in the ongoing labour dispute with the province.
Other school boards hit by strikes Tuesday were Peel, Durham, Waterloo, Greater Essex, Grand Erie and Lambton Kent in southern Ontario and the Near North board in central Ontario.
The ETFO said the one-day strikes are to protest controversial legislation that gives the provincial government the power to end strikes and impose a collective agreement on the teachers.
Federation president Sam Hammond said Education Minister Laurel Broten can end the rotating strikes by repealing Bill 115 and letting local bargaining proceed without interference.
But Broten, who said she was "disappointed" by the continuing job action, added the federation was in a legal strike position and that the government decided to let the strikes happen as long as they were only for one day at each board.
"It was a difficult decision to allow a strike action to take place because we had to carefully weigh the balance of legal strike action and the needs of students and parents to have stability in their schools," she said Tuesday.
"They are obviously two competing interests, and we need to get that balance right."
Premier Dalton McGuinty weighed in on the walkouts on in a morning appearance on CityTV's "Breakfast Television," defending his government's position as a financial necessity.
"It's gotten a little sticky, that's unfortunate, but I am convinced we are doing the right thing for the long term," he said.
He urged teachers to return to the bargaining table and thanked parents for "all the extra efforts they are making to manage this circumstance."
"Thankfully, it's just the one day," he added.
To help parents in Toronto deal with the strike, the Royal Ontario Museum offered a kids day for children aged five to 14 — at a cost of $65 per child. Second City opened the doors of its Toronto training centre offering a one-day youth improv camp for students in Grades 1 to 8 for $20 per student.
Although the governing Liberals have the power to end the teachers' strikes, they've said they will allow legal one-day walkouts to occur in all school boards if 72-hours notice is provided.
If the strikes extend beyond a day, however, the government said it has already prepared the necessary legal documents to end them.
Meanwhile, Progressive Conservative education critic Lisa MacLeod called on Broten to use Bill 115 — which the Tories supported — to end the strikes.
"The McGuinty Liberals have the ability, the power and the authority to end these strikes today," McLeod said in a news conference Tuesday.
"They chose to ignore their legislation in Bill 115 when these strikes started, we're simply asking them to invoke their own law," she added.
Broten said a balanced approach is a more appropriate way of dealing with the situation, adding that once the one-day strike is over, students will be back in their classrooms as normal.
"We felt that one day and one day only and holding the elementary teachers' federation to their commitment that it would only be one day was the right balance."
In Toronto, a massive rally with thousands of teachers was held outside the office of the Toronto District School Board. Earlier, in Durham Region, hundreds of teachers gathered for a rally at Memorial Park in Oshawa.
On Wednesday, more than 4,800 teachers with the Bluewater, Algoma, and Halton school boards will be staging a one-day walkout.
Thursday's walkouts involve the Thames Valley board, which includes London, Woodstock and St. Thomas in southwestern Ontario, the Limestone board in the Kingston area of eastern Ontario, the Superior-Greenstone board in northwestern Ontario and the Upper Canada board in the Brockville area of eastern Ontario.
Broten confirmed that with Thursday's planned action, every public school board in Ontario will have been hit by a one-day strike.
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