When teachers have higher cognitive skills, their students perform better academically, according to a new study that compared data from 31 countries.
And teachers’ cognitive skills differ widely across the world, with teachers in the United States performing worse than the average teacher in numeracy and slightly better than the average in literacy. Similarly, U.S. students perform below the average score in math and about average in reading.
Notably, teachers have stronger cognitive skills—and their students perform better in math and reading—in countries that pay teachers more, like in Ireland, Canada, and Finland. Teachers’ cognitive skills were measured by an international survey of adults’ information-processing skills, like literacy, numeracy, and problem-solving.
“This is the first time I’ve got conventional wisdom on my side,” joked Eric Hanushek, a senior fellow at the Hoover Institution of Stanford University, and one of the study’s authors. “We all think that having smarter teachers will in fact lead to better performance. ... What we show, I think, is that countries that have smarter teachers ... make an active choice to hire teachers from higher up in the distribution of college graduates.”
The study, published in the journal Education Next, examines data from the Organization for Economic Cooperation and Development. The researchers looked at OECD’s Program for the International Assessment of Adult Competencies survey data to gauge the reading and math skills of about 6,400 test-takers who work as teachers, as well as student-achievement data from the Program for International Student Assessment.
The researchers compared teachers’ math and reading skills in each of the 31 countries to the skills of other adult workers in their country and to the skills of teachers in other countries. They also examined whether students score higher on PISA, on average, in countries where the median teacher has stronger math and reading skills.
They found that increasing teachers’ math skills by one standard deviation increases student performance by nearly 15 percent of a standard deviation on the PISA math test. The effect of increasing teachers’ literacy skills on students’ reading performance is slightly smaller, but still positive.
(Researchers conducted a series of controls to determine that the relationship between teacher cognitive skills and student performance is not driven by overall skill levels in the country, but specifically what teachers know.)
The researchers also found the impact of teachers’ cognitive skills is somewhat larger for low-income students than their more-affluent peers, particularly in reading.
“Schools are just inherently more important for low-income kids,” Hanushek said. "[In wealthy households], you have the ability to make up for less-good instruction, whereas lower-income families, on average, are not as prepared or ready to make up for what goes on in schools.”
How Can We Create a Smarter Teacher Workforce?
Teachers perform better than the median college graduate in countries like Finland, Singapore, Ireland, and Chile, the study found. Finland and Singapore in particular have been praised by education scholars for their work on building a high-quality teaching force. For example, Finnish teacher-preparation programs only select about 10 percent of applicants—which the Finnish minister of education told Education Week is because “teachers are so respected in our society.”
To match the cognitive skills of Finnish teachers, the United States would need to recruit its median math teacher from the 74th percentile of the college distribution instead of the current 47th percentile, and its median reading teacher from the 71st percentile instead of the 51st, the study found.
Making teacher-prep programs more selective has been a controversial policy goal in this country. The Council for Accreditation of Educator Preparation, for instance, originally set a standard that would require colleges to admit a group of candidates with an average 3.0 GPA and who held scores averaging in the top half on nationally normed achievement assessments. But that standard received enormous pushback from universities. Many in the field said that GPA doesn’t necessarily determine who will be a good teacher. And there was a diversity concern, too: Black and Latino candidates tend to have lower scores than their white and Asian counterparts on traditional selectivity metrics, such as GPAs and SAT scores. (CAEP eventually softened the requirement to say programs could meet the average 3.0 GPA requirement at admissions or by the time candidates graduate.)
Instead of focusing on pipeline policies like those, the researchers write that increasing teacher salaries would be a way to expand the pool of potential teachers. Research shows that few high-achieving students want to become teachers.
“I think the U.S. has chosen a really bad equilibrium in that we really do underpay our teachers,” Hanushek said, adding that U.S. teachers are paid 22 percent less than comparably experienced and skilled college graduates doing other jobs. “Then we get people who are not very high up in the distribution of college graduates.”
The study found clear evidence that higher teacher pay is associated with an increase in teachers’ cognitive skills—which, in turn, is associated with better student performance.
Teachers across the country recently have walked out of their classrooms in protest of low wages. The national average teacher salary is $55,100, according to 2015-16 federal data, and that varies widely between states.
Still, Hanushek said raising teacher salaries across the board might not achieve the desired results. “Bad teachers like more money as much as good teachers,” he said.
Instead, he recommends that policymakers work to ensure that higher salaries go to the most effective teachers.
Performance-based compensation is a reform that has fallen out of favor in the wave of teacher activism—teachers have gone on strike for across-the-board raises, and paying good teachers more has rarely entered in the conversation. (The one exception is in Denver, where the teacher strike that ended last week was centered on performance-based compensation.)
An Education Week analysis of State of the State addresses found that 17 governors so far this year have recommended that their state boost teachers’ pay—but only Texas Gov. Greg Abbott has suggested a merit-based model.
“I don’t think we can keep saying we’ve got the best teachers in the world,” Hanushek said. “We can’t keep underpaying teachers and ignoring teacher effectiveness in the classroom—it’s got to be competitive.”
Image via Getty, chart via Education Next
A version of this news article first appeared in the Teacher Beat blog.