Science and technology are upending how we learn. We separate the science from the snake oil and look at how parents, teachers, and policymakers respond.

The results are in for the OECD’s latest global test of 15-year-olds in math, science, and reading. The test, known as PISA (for Programme for International Student Assessment), is administered every three years and used—by some—to measure which countries are best preparing their students for the future.

Once again, Asian countries came out on top. In the latest test, China and Singapore ranked first and second, respectively, in math, science, and reading. Elsewhere, Estonia is noteworthy for its performance, ranking highly in all three subjects.

Mainland China is measured by taking an average of four provinces: Beijing, Shanghai, Jiangsu, and Zhejiang. Some argue that “China” shouldn’t be represented by just a few eastern regions, but the OECD says that each of them is comparable in size to many Western countries, and have a combined population of over 180 million. (Hong Kong, Macau, and Taiwan also appear separately in the rankings.)

What’s more, in the four provinces of mainland China that participated in the study, the 10% most disadvantaged students showed better reading skills than the most advantaged students in some countries, and better performance than the average student in OECD countries.

The OECD is trying to change the test to be about more than academics, in part to encourage countries to view education beyond traditional subjects. In the latest test, it assessed global competency, asking students to express how they relate to others and what they think of their lives and their future; in the next test, in 2021, it will assess creative thinking.

It also regularly asks students questions about their wellbeing, including measures of belonging and life satisfaction.

Results from the latest wellbeing study are concerning. Across OECD countries, only about two-thirds of students said that they were satisfied with their lives, a share that shrank by five percentage points between 2015 and 2018. Almost a quarter of students reported being bullied at least a few times a month and 6% reported always feeling sad. In almost every education system, girls expressed a greater fear of failure than boys, even when they outperformed boys in reading by a large margin.

The OECD says the point of PISA is to help education systems improve by offering data and transparency. “The aim with PISA was not to create another layer of top-down accountability, but to help schools and policy makers shift from looking upwards within the bureaucracy towards looking outwards to the next teacher, the next school, the next country,” wrote Andreas Schleicher in the report with the latest batch of test results.

But PISA has its detractors, including those who believe it tries to do too much, that it distorts what is important, and creates an arms race in education. In 2014, more than 100 academics around the world called for a moratorium on PISA testing, citing the problem Schleicher claims he wants to fix: An over-reliance on testing and a tendency to recommend simple solutions for complex problems. They wrote:

The new Pisa regime, with its continuous cycle of global testing, harms our children and impoverishes our classrooms, as it inevitably involves more and longer batteries of multiple-choice testing, more scripted ‘vendor’-made lessons, and less autonomy for teachers.

Angel Gurría, secretary-general of the OECD, disagrees. “PISA is not only the world’s most comprehensive and reliable indicator of students’ capabilities, it is also a powerful tool that countries and economies can use to fine-tune their education policies,” he wrote in the report.