A recent last-minute tentative deal between the Ford government and the CUPE union representing school support staff barely averted what would have been a highly-disruptive strike. As a result, education policy remains front of mind for many Ontarians.

In last week’s column, I shared results of a recent international analysis of spending on education and student performance, which found that in affluent countries such as Canada—that already spend a lot on education—there are generally “diminishing returns” on further spending increases. In other words, after a certain point, you get less “bang for the buck” for any additional spending.

Some may wonder how this can be so, but a new study by Derek Allison, professor emeritus of education at the University of Western Ontario, examines the relationship between class size and student performance in Canada. In short, his study compares student performance in provinces with larger average class sizes to provinces with smaller average class sizes to see if the latter group outperforms the former.

The study’s findings provide no fodder for advocates who argue that spending more money to get class sizes down will help students perform better. In fact, during the period studied, Ontario had the smallest class sizes—and some of the worst scores in key subjects reading, science and math.

In addition to comparing Canadian provinces, the study reviews the international evidence, reaching similar conclusions—relatively small positive benefits from smaller classes in the lower grades and inconclusive results for higher grades. As such, spending more money to make classes smaller, especially in higher grades, is a questionable strategy to help students succeed.

Of course, this new research is highly relevant to Ontario at this moment, as the Ford government has decided to gradually increase secondary school class sizes to save money. Critics claim this move could have substantial negative outcomes for students, but again, Prof. Allison’s research suggests these concerns are not well-founded. The international evidence provides little evidence that the move will, in and of itself, hurt student performance outcomes while we can see just by looking at other provinces such as British Columbia, Alberta and Quebec that larger classes than we have now in Ontario are entirely consistent with improved student outcomes.

Everybody wants Ontario’s schools to be excellent and everyone wants student performance to be strong. However, there’s little evidence that additional educational spending in Ontario will actually improve student outcomes on average. Because, as noted in Prof. Allison’s research, while making classes smaller is generally an expensive policy choice, it’s not one that (especially in the higher grades) is likely to have a significant positive impact on student performance in the classroom.

Hopefully, policymakers in Ontario will use the research evidence to form future education policy with students in mind.