Great teachers have a huge impact on kids. Research has shown that students with highly effective teachers (those in the 90th percentile) learn 1.5 years’ worth of material in a year, while students with teachers in the 10th percentile learn just half a years’ worth of material in the same period. “No other attribute of schools comes close to having this much influence on student achievement,” Eric Hanushek, an economist at Stanford University, told the Economist.
The students who stand to benefit the most from the most effective teachers are those in disadvantaged schools. But a new report from the OECD finds that in many countries, including France, the Netherlands and the US, just the opposite is happening: Disadvantaged schools have less qualified or less experienced teachers, compared to advantaged schools. Instead, many of these countries attempt to address inequity by creating smaller classes or lower student-teacher ratios for worse-off schools.
To help poor students, countries should “assign high-quality teachers, and not just more teachers, to the most challenging schools,” said Andreas Schleicher, director of the OECD’s Education and Skills group. “Teacher policies have a critical role to play in delivering a future for millions who currently may struggle to have one.”
The OECD report examines the policies that help attract high-quality teachers and develop and retain them, as well as how to allocate them to different schools. High-performing systems—those which perform well on international tests—tend to treat teaching as a high-status profession for which one needs rigorous, ongoing training. It’s more competitive to become a teacher than a doctor in Finland; in Korea, teachers are paid very well compared to others with similar levels of education. And because of both financial incentives and government requirements, socio-economically disadvantaged students in Japan and Korea are at least as likely as their advantaged peers to be taught by the best teachers, as measured by factors like years of experience, certification, and, for science teachers, having a university degree with a major in science).
According to the report, there’s some overlap between the countries with the most-qualified teachers and those that perform the best on international tests:
While many conversations about education reform still tend to focus on class size, many believe this is misplaced, including John Hattie, director of the Melbourne Education Research Institute at the University of Melbourne. Hattie has analyzed over 65,000 research papers to see what education interventions have the biggest effect on student performance. Class size is not one the significant ones; building better teachers and giving better feedback to students are.
Another misplaced hope is that more money will solve the problem. As Hanushek points out, school expenditures per student have more than doubled since 1970, while graduates’ achievement has remained mostly flat.
Countries that invest more in improving students’ academic performance can reap big benefits down the line. Hanushek also analyzed the impact of test scores on GDP growth and found it was huge. Using the example of Canada, which ranked ninth on the 2015 Program for International Student Assessment’s math tests (compared to the US’s paltry 39th place finish), he says that if the US were to close half the gap with Canada, it would “raise the average US gross domestic product 7 percent across the 21st century—more than enough to pay for projected fiscal problems with Medicare and Social Security benefits.”
The OECD report says the best-performing school systems had three things in common when it came to teachers: Most had a required and extended period of on-the-job training during which they received feedback and support from mentors in a formalized program; most professional development was in-house, rather than imported by experts; and teacher evaluation focused on useful feedback for improvement. Also, teachers felt valued in society.
But the report was quick to note that policy matters. “Contrary to what is often assumed, high-performing systems do not enjoy a natural privilege simply due to a traditional respect for teachers; they have also built a high-quality teaching force as a result of deliberate policy choices, carefully implemented over time.”