Ontario's elementary school children are saying goodbye to the classroom for the summer break this week, but they could see labour unrest when they return in the fall.

The Elementary Teachers' Federation of Ontario, the union representing 73,000 members, has walked away from contract talks with the province.

One sticking point at hand is the funding gap between elementary and secondary students. High school students receive an average $700 more than the younger pupils.

"That's an issue that impacts elementary students in this province every day, and it's one that our teachers wish to see resolved," ETFO president David Clegg told CTV Toronto.

Clegg says teachers are frustrated by the situation, and he says the government is missing an opportunity to reverse the "historical discrimination" against elementary students and teachers and improve children's learning conditions.

Another point of contention in the dispute surrounds the amount of preparation time teachers receive. The union is pushing for 375 minutes a week, up from their current 240 minutes, CTV Toronto's Paul Bliss reported.

The ETFO, which educates more than 1 million students, would also like the province to hire more teachers.

Clegg wouldn't comment yet about job action or a possible strike in the fall, but most teachers' collective agreements expire on Aug. 31.

Education Minister Kathleen Wynne says it's unfortunate the teachers' union has walked away from talks.

"They've decided at this point that they don't want to continue the conversation and our position is that we will welcome them back to the table at any point," she told CTV Toronto.

Wynne says considering the economic uncertainty, the Ontario government is offering a good deal in the contract discussions, including an annual three per cent raise over the next four years.

Dalton McGuinty's Liberal government has enjoyed labour peace at its schools since taking power in 2003. There hasn't been a teachers' strike over that time, partly because the province signed the teachers to four-year contracts.

With a report from CTV Toronto's Paul Bliss