Parents and students might have a little extra time to do back-to-school shopping, as the start of the school year may be delayed due to a possible teacher's strike.

Representatives from the Elementary Teacher's Federation of Ontario say they may face labour "limbo" because the province will not meet student funding demands.

The federation says there is not enough funding for elementary students, leading to larger class sizes for students in Grades 4 to 8.

But Education Minister Kathleen Wynne says the province has come up with a fair funding formula, saying both parties need to come to an agreement at the bargaining table.

"Many of the things we are proposing would in fact result in that gap continuing to close," says Wynne.

One of those proposals is a three per cent raise each year over four years for teachers in Grades 4 to 8.

But union president David Clegg says Wynne is sending a mixed message to teachers, who won't sign a long-term agreement that doesn't address the funding gap.

All collective agreements for Ontario's 73,000 elementary public school teachers expire on Aug. 31.

With files from The Canadian Press.