TORONTO -- The Elementary Teachers' Federation of Ontario says it will bring its strikes to the Durham, Lambton Kent and Algoma school boards on Thursday.

The job action will be part of a second week of rotating walkouts from the union representing 83,000 public elementary and occasional teachers in Ontario.

The strike will add to tensions between the province and its four major teachers' unions, which have been without contracts since August.

Union president Sam Hammond says the teachers will strike because they are dedicated to improving the lack of support for children with special needs and large class sizes.

The union's members in Simcoe, Waterloo and Keewatin-Patricia are set to strike on Jan. 27 and teachers in Kawartha Pine Ridge, Hastings-Prince Edward, Upper Grand, Moosenee and Moose Factory will follow on Jan. 28.

Teachers in Greater Essex, Limestone, Near North and Upper Canada will hit the picket lines on Jan. 29.