How Air Quality Can Sink Student Test Scores

American 8-year-olds are paralyzed with anxiety over the standardized tests that have become increasingly common: To implement more uniform, quality education, students in the U.S. are being tested to often more rigorous national standards. Join the club. Other countries have relied on high-stakes testing for years. Until the 1970s, the 11+ exam in the U.K. determined whether an 11-year-old was college material.

The United Kingdom still relies on testing to determine who goes to college, but students aren’t ruled out until well into high school. Overall, sealing children’s fates so early has fallen out of fashion. But in many countries college admission is still based solely on exams, tests that are considered to be an objective and fair way to screen and sort teenagers. It turns out high-stakes testing is anything but—it tends to discourage the most vulnerable teenagers, with lasting consequences.

In addition to the U.K., Israel, France, Germany, and Japan also use a single exam (or series of them) to determine whether high school students go to college and what they study there. Historically the governments of these countries have paid for university education, which served as justification for a fair and efficient way to decide who deserved a state-sponsored college education. Since far more Americans finance their own educations, colleges were never pressured to adhere to a single strict admission criteria. The U.S. version of a national test, the SAT (or ACT), is only part of an application, which can also include grades, essays, activities, and other considerations.

The American way is more arbitrary, and so it seems less meritocratic. But a new paper by Israeli economists Victor Lavy, Avraham Ebenstein, and Sefi Roth finds high-stakes testing, like the American system, also favors the rich. The authors looked at the Israeli admissions system, where the Bagrut exam determines university admissions. They took the test scores of 55,873 students at 712 schools from 2000 to 2002, and the students’ earnings 10 years later. They then compared test scores and future wages with the level of ambient air pollution on the test days. Ambient pollution is associated with impaired cognitive performance, especially for asthmatics.

The economists estimated elevated levels of pollution (defined as an additional 10 PM_2.5 units of exposure) lowered test scores by 0.23 percent. That might mean 2 percent lower wages a decade later. The consequences were greater for weaker students, students from low-income families, and girls. The authors speculated that more confident and well-connected students manage to persevere in a way their more vulnerable peers don’t. Richer parents might send their children abroad or to a school that doesn’t require the test. More tenacious, often male, students go to whichever college will take them and still pursue their career ambitions. The authors concluded: “If male students are committed to participating in a lucrative profession, they will perhaps be less dissuaded by a poor score.”

The problem with high-stakes testing is that there exists an element of randomness you can’t control. Most people experience bad luck at some point in their lives. Whether that luck has catastrophic consequences comes down to personality or the resources to throw enough money at the problem. High-stakes testing may teach teenagers that life lesson too soon.