Harvard professor urges Finland to collect education data to address Pisa decline

A Harvard professor widely tipped as a future Nobel laureate has warned that Finland cannot reverse its collapsing Pisa scores without systematically collecting data on teachers and learning outcomes, Yle reports.

Raj Chetty, who became a Harvard economics professor at 28 and has already won the discipline’s prestigious John Bates Clark Medal, said Finland’s current data makes it impossible to determine why its once-top-ranking Pisa performance has plummeted to the OECD average.

Chetty, visiting Finland at the invitation of the Yrjö Jahnsson Foundation, said he once frequently cited Finland as a model of high-quality education, with well-trained, respected teachers contributing to strong social mobility. He expressed surprise at the steep decline in Finnish learning outcomes, noting that such a sharp drop from the top tier is rare.

Finland’s Pisa scores have fallen rapidly from the top of international rankings to the OECD average, while achievement gaps between socioeconomic groups, genders, and students with domestic versus immigrant backgrounds have widened. The country has also fallen behind other Western nations in higher education attainment.

Chetty, known for large-scale causal research linking education policy to social mobility, said Finland must begin collecting more comprehensive data to identify effective solutions. He recommended introducing national, uniformly graded tests to assess student performance, even if the results are not used for individual grading.

Such tests, already used in other Nordic countries every few years, would provide essential data for education policy development. Finland currently relies on random samples that prevent causal analysis or comparisons across schools, regions, or time.

Chetty acknowledged concerns that national tests could increase school shopping and deepen inequalities if parents avoid lower-performing schools. However, he argued the solution is not to reject testing but to address emerging problems, such as by allocating additional resources, reducing class sizes, or expanding special education in struggling schools.

Without better data, Chetty said, Finland will continue to guess at the causes of its education decline rather than implement evidence-based reforms.