The elementary school teachers' union is giving formal notice of its first strike.
A one-day walkout will be held in the Avon Maitland and Ontario North East School Districts on Monday.
The board confirmed that all of its 28 schools in the Ontario North East district will be closed.
The notice was given by the Elementary Teachers' Federation of Ontario Wednesday afternoon.
This comes right after the elementary teachers union voted in favour of a political protest if Education Minister Laurel Broten blocks their legal strike with Bill 115.
The controversial law freezes teacher's wages and can put a stop to strike action.
"I understand that notice has been given to the Avon Maitland and Ontario North East District School Boards by ETFO locals for a one-day strike on Monday, December 10th," Minister Laurel Broten said in a statement released Wednesday.
"I understand parents are concerned about the impact of this on their families. I am taking the time to consider all the options available to our government and will provide an update tomorrow morning to parents in these two communities. I know that parents hope that the ETFO leadership will reconsider this unnecessary action and that they will focus on putting students first."
Broten will be speaking at 9:30 a.m. Thursday.