In 1967, on the first international comparison of educational achievement in math, the United States ranked 11 out of 12 nations. Students in Germany, England, France and Japan all scored ahead of students in the U.S.. The only country behind the U.S. was Sweden. No one was surprised. A Washington Post news article explained that U.S. teachers weren’t as well trained in math pedagogy and that American society didn’t value mathematical achievement as much as other countries.
After the release of the latest 2018 rankings by the Programme for International Student Assessment, or PISA, earlier in December 2019, there was considerable hand wringing and consternation but the result wasn’t much different. The U.S. still ranks behind the same group of countries, with the exceptions of Israel, which has slipped below, and Sweden, which has risen above the U.S. In math, the U.S. ranks 36th out of the 79 countries and regions that participate in the test.
It’s worth noting that the U.S. Department of Education considers the U.S. ranking to be 30th, not 36th. That’s because some of the numerically higher scores are so close that the National Center for Education Statistics calculates them to be statistically equivalent. And not all of the 79 geographic entities are countries. In some cases, autonomous regions, such as Hong Kong, participate separately from their countries. The Organisation for International Co-operation and Development (OECD), which runs PISA, also allows partial participation for some nations. The top rank in the world is held by a group of four provinces within China (Beijing, Shanghai, Jiangsu and Zhejiang).
But however you count it, U.S. math performance is below the international average.
“What surprises me is how stable U.S. performance is,” said Tom Loveless, an education expert who was formerly at the Brookings Institution. “The scores have always been mediocre.”
The U.S. performs relatively better in reading, average instead of below average. It ranks 13th out of the 79 countries and regions, according to the 2018 PISA scores in reading. As with math, U.S. performance hasn’t changed much since the first PISA tests in 2000. Today’s scores in reading and math aren’t statistically different from when PISA started testing the subjects in the early 2000’s.
The latest PISA scores reinforce the results from the 2019 National Assessment of Educational Progress (NAEP) test of math and reading, which U.S. fourth and eighth graders take every two years. Those results, released in October 2019, also found that U.S. achievement hasn’t progressed over the past decade and, for low-performing students, was the same as 30 years ago. The international PISA test is taken by older students, 15-year-olds, every three years. The majority of U.S. test takers are at the beginning of their high school sophomore year.
Amid the long-term stagnation, there is an important change to note. Inequality is growing. Peggy Carr, associate commissioner of the National Center for Education Statistics (NCES) points out that both exams are showing a widening achievement gap between high- and low-performing students. One in five American 15-year-olds, 19 percent, scored so low on the PISA test that they had difficulty with basic aspects of reading, such as identifying the main ideas in a text of moderate length.
But the inequality story is a nuanced one. Part of the inequality is between schools with students at wealthier schools posting much higher test scores than students at schools with large numbers of disadvantaged students. But the vast majority of educational inequality in America is inside each school, according to the PISA test score report. Statisticians mathematically teased out inequality between schools versus within each school and found that, in the U.S., only 20 percent of the variation in student performance is between schools. The remaining 80 percent is inside each school.
I wanted to understand this more and talked with Miyako Ikeda, a Paris-based senior analyst in charge of PISA data analysis at the OECD. For readers who want to geek out with me, here’s the explanation. Imagine five schools, each with 10 students. Students in the first school come from the poorest families and students in the fifth school come from the wealthiest. The other three schools lie between the two extremes. If you calculate the average test score for the 10 students in each school, you would see that the average test score for each rises with wealth. In the U.S., 93 points separate the average score in the poorest schools from the wealthiest. That’s about three grade levels — the difference between 10th grade achievement and 7th grade achievement.
But what’s interesting is that the difference in test scores among the top performing and lowest performing students in each school is much greater. In a simplified diagram of the U.S. that Ikeda drew for me, “A” on the right, you can see that the top performing students in the most disadvantaged schools are scoring as well as average students in the “best” schools. Each “x” represents a student.
This is a sharp contrast with other schools systems around the world. In Germany, for example, there is much less variation in each school. Student test scores are clustered closely together under each roof. But there are greater differences between schools with the least advantaged schools scoring much lower than the wealthiest schools . Germany is closer to something like “B” in the diagram. In this case, no one in the least advantaged schools is approaching the the scores of the most advantaged schools.
Why the U.S. has so much inequality inside each school is up for debate. Even if the family incomes are similar in each school, American schools might have more cultural diversity with some families emphasizing the importance education more than others. In other cases, there might be a wide range of incomes in a large high school and student performance mirrors that wide range.
Andreas Schleicher, director for education and skills at OECD, hypothesizes that the common practice of “tracking” or separating more advanced students into more challenging classes is to blame. Other scholars have come to the same conclusion in their analysis of international test scores. If what the students are learning in their classrooms are different, you’d expect the test scores to be different too.
Although the debate over interpreting the data is likely to continue, one thing seems clear. We need to rethink reform. While it is vital to fix dysfunctional schools where too few students can read well and add fractions, these PISA test results show that we also need to understand what goes wrong at our most functional and revered suburban schools where the bottom students get left behind.
This story about PISA rankings 2018 was written by Jill Barshay and produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education. Sign up for the Hechinger newsletter.