The Toronto District School Board, Ontario's largest, said elementary school absences increased by 144 per cent yesterday compared to Monday of the previous week.
And at least one elementary school in midtown Toronto, Thorncliffe Park Public, had an absentee rate of more than 90 per cent.
Many parents object to the updated curriculum based on religious grounds.
Opponents argue that the new program, which will teach students about concepts including gender identity, sexual orientation and masturbation, does not mesh with their values and is inappropriate for school-age children.
Curriculum supporters contend the updated guidelines bring Ontario in line with the rest of Canada.
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