Nova Scotia relies much more heavily on the public school system than provinces such as Quebec.
Ontario union leaders say proposed increases to the number of students per teacher will hurt the quality of education in the province.
Provinces PISA scores in all three subjects are below the national average.
Quebec and B.C. have fairly simple public education systems, relying on independent schools to provide the bulk of educational choice.
Spending on public schools in Ontario increased from $25.5 billion to $27.9 billion.
Three years later B.C. has fallen to fourth place in reading, science and math.