Over the past decade, the OECD Programme for International Student Assessment, PISA, has become the world’s premier yardstick for evaluating the quality, equity and efficiency of school systems. But the evidence base that PISA has produced goes well beyond statistical benchmarking. By identifying the characteristics of high-performing education systems, PISA allows governments and educators to identify effective policies that they can then adapt to their local contexts.

Schools are not just places where students acquire academic skills; they also help students become more resilient in the face of adversity, feel more connected with the people around them, and aim higher in their aspirations for their future. Not least, schools are the first place where children experience society in all its facets, and those experiences can have a profound influence on students’ attitudes and behaviour in life.

Schools are not only places where students acquire academic skills; they are also where children develop many of the social and emotional skills that they need to thrive. Schools that nurture children’s development in these ways help students attain a sense of control over – and satisfaction with – their life. They can help students become more resilient in the face of adversity, feel more connected with the people around them, and aim higher in their aspirations for their future. In other words, what happens in school is crucial for well-being. Students’ well-being, as defined in this report, refers to the psychological, cognitive, social and physical qualities that students need to live a happy and fulfilling life.

“What is important for citizens to know and be able to do?” In response to that question and to the need for internationally comparable evidence on student performance, the Organisation for Economic Co-operation and Development (OECD) launched the triennial survey of 15-year-old students around the world known as the Programme for International Students Assessment, or PISA. PISA assesses the extent to which 15-year-old students, near the end of their compulsory education, have acquired key knowledge and skills that are essential for full participation in modern societies. The assessment focuses on the core school subjects of science, reading and mathematics. Students’ proficiency in an innovative domain is also assessed (in 2015, this domain is collaborative problem solving). The assessment does not just ascertain whether students can reproduce knowledge; it also examines how well students can extrapolate from what they have learned and can apply that knowledge in unfamiliar settings, both in and outside of school. This approach reflects the fact that modern economies reward individuals not for what they know, but for what they can do with what they know.