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This country has the world’s smartest students

Chinese students have come out on top in an international standardized test covering mathematics, reading and science, far outscoring their U.S. counterparts who achieved below average marks in two out of three subjects.

The results of the 2012 Program for International Student Assessment (PISA) – which measures literacy of 15-year-old students in three subject areas – highlight the gap in the academic performance among pupils in Eastern and Western nations.

Students from Shanghai, Singapore and Hong Kong were the top three scorers – attaining results significantly above the OECD (Organization for Economic Co-operation and Development) average of 494 in mathematics, 496 in reading and 501 in science.

XiXinXing | Getty Images

The average score in Shanghai was 613 on the mathematics test, 570 on the reading test, and 580 on the science test.

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American students, in comparison, trailed behind their peers in economic rival China as well as Western economic powers such as Germany, France and the United Kingdom.

In the U.S., the average score was 481 on the mathematics test, 498 on the reading test, and 497 on the science test.

The test, which is taken by more than 500,000 15-year-old students from randomly selected schools in 65 countries, is conducted every three years and used to evaluate education systems worldwide. It lasts two hours and includes a mixture of open-ended and multiple-choice questions.

On a global level, findings of the assessment revealed that the highest performing school systems are those that allocate educational resources equitably among advantaged and disadvantaged schools and that grant more autonomy over curricula and assessments to individual schools.

Focus on mathematics

While the assessment covers three subjects, there is a particular focus area each time it is conducted, this year being mathematics.

"Now that computer technology is accessible to virtually all and is increasingly capable of carrying out routine processes, jobs that do not require mathematical skills are becoming scarcer," the report said.

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"It is now clear that students' mastery of mathematics must include the capacity to formulate problems mathematically and interpret results," it added.

PISA results showed wide differences between students' mathematics skills, with 245 score points separating the highest (China) and lowest (Peru) averages.

The report also revealed worrying gender differences in students' attitudes towards mathematics.

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"While the average girl underperforms in mathematics compared with the average boy, the gender gap in favor of boys is even wider among the highest-achieving students," the report said.

"Even when girls perform as well as boys in mathematics, they report less perseverance, less motivation to learn mathematics, less belief in their own mathematics skills, and higher levels of anxiety about mathematics," it added.

—By CNBC's Ansuya Harjani; Follow her on Twitter @Ansuya_H