Shanghai again ranked first for mathematics, science and reading in a three-yearly report on global education as students in Asia continued to outshine their Western counterparts.

They also spent more time doing homework than their peers in the 65 countries and regions which took part in the tests for the Paris-based Organization for Economic Cooperation and Development.

Its PISA report (Program for International Student Assessment) is the single largest study of global schooling.

It is highly influential, with participating countries and regions representing more than 80 percent of the global economy and often adapting policy in response to the findings.

The first PISA survey was carried out in 2000, and Shanghai joined in 2009, coming first in the three categories.

Around 6,400 students from 155 schools in Shanghai took part in the latest assessment in April last year. Globally, about half a million 15-year-olds took part.

The tests are based on a 1,000-point scale.

In mathematics, average scores ranged from 368 in Peru to 613 in Shanghai. The US average was 481, below the global average of 494. Singapore and Hong Kong took second and third with scores of 573 and 561.

In science, average scores ranged from 373 in Peru to 580 in Shanghai. The US scored 497. The global average was 501.

In reading, average scores ranged from 384 in Peru to 570 in Shanghai. The US scored 498, just above the global 496.

“The results are very inspiring. While it is good to see our students have performed so well, it is worth thinking if we really need so many students to be so good at mathematics,” said Zhang Minxuan, leader of the Shanghai PISA program and president of Shanghai Normal University.

Shanghai students reported an average of 13.8 hours every week doing school assignments, the highest and almost three times the average 4.9 hours.

Zhang said an analysis showed the optimal time for students to do homework is 11 hours per week including weekends. “We found that students who spent more than 11 hours on homework didn’t make significant progress, which deprived their time of discovering other talents.”

The mathematics test was divided into several parts to examine students’ skills to solve real-world questions using a knowledge of geometry, algebra, calculation and statistics. Shanghai students performed well in translating a real-world problem into a mathematics problem but were poorer at explaining the results.

Zhang attributed Shanghai’s students’ good performance in mathematics to more chances to learn the subject, personal ability and family background.

Boys and girls have a similar performance in mathematics but girls were more modest in assessing their ability.

“We should encourage girl students to think they can do math as good as boys and help them build confidence,” Zhang said.

In reading and science, the score gap between boys and girls in Shanghai has narrowed compared to 2009, Zhang said.

He said the results showed that Shanghai’s education was well-balanced as the gap between low proficiency and high proficiency was smaller than the average level.

Zhang said the PISA results had given thoughtful hints on how to provide a balanced education for students.

Schools are advised to give fewer after-school assignments and reduce homework so that students can have more time for individual development. For teachers, they should think about how to help students use mathematics skills to solve real problems instead of learning how to solve a math problem only. It is also suggested that parents not overburden their children with after-school tutoring.