The value of standardized tests in measuring and improving student academic performance is often a point of dispute. Opponents of the tests say they are unhelpful, an unreliable measure of educational quality and a waste of time. Moreover, according to teacher unions, the data they generate are “entrenching both real and perceived inequities”—presumably because they do not show equal academic performance across all schools.

Yet in developed economies around the world, standardized tests are in wide use. Across the member countries of the Organisation for Economic Co-operation and Development (OECD), a survey of school principals found that approximately three-quarters of 15-year-old students attend schools that use mandatory standardized tests at least once annually.

In Canada, standardized tests are used more frequently than the OECD average but less frequently than in either the United Kingdom, where, according to the survey, “all school principals reported that such tests are used once a year,” or the United States, where “almost all students” are assessed with a mandatory standardized test at least once annually.

The tests are used for a wide variety of purposes. The majority of school principals in Canada and across the OECD report that standardized tests help them monitor their school’s progress over time, compare it to other schools and to regional or national performance, guide student learning, inform parents about their children’s progress, and identify how instruction or the curriculum could be improved.

Of course, just because most schools in developed countries use these tests does not necessarily make them a good idea. As parents often ask their children: “If all your friends jumped off a bridge, would you jump, too?” Governments everywhere make plenty of errors, and maybe standardized tests are among them.

But if there’s an institution anywhere that is less trustworthy on education policy than governments, it’s surely teacher unions. Though governments regularly make horrible policy errors politicians at least have some incentive to get things right. They do often find it advantageous to appease unions and other special interest groups at the expense of the general public but there’s a limit to that sort of thing. Parents and taxpayers are voters, too.

By contrast, the teacher unions have much weaker incentives to get education policy right. Their mandate is to secure the best possible compensation and job security for teachers, regardless of teacher competence or job performance. It is, in other words, the mission of a teacher union to protect teachers from being held accountable—even if the quality of education suffers as a result.

In Ontario, for example, the Education Quality and Accountability Office found that even before the pandemic disrupted schooling, 42 per cent of Third Grade students and 52 per cent of students in Sixth Grade failed to meet provincial standards in mathematics. No wonder the Elementary Teachers’ Federation of Ontario has repeatedly insisted that tests are worthless and/or harmful and should be abolished.

At bottom, it’s not the teacher unions, nor the school principals, nor education bureaucrats that should make decisions about standardized tests. The purpose of schooling is to serve families, so the parents should decide. A survey this year found that 84 per cent of Canadian parents favour standardized tests in K-12. Let’s ignore the unions and keep the tests.