The OECD's triennial study of 15 year-old students across the world found that the four Chinese provinces tested -- Beijing, Shanghai, Jiangsu and Zhejiang -- outperformed in science and mathematics, even if household income is well below members' average. In reading, the 10% most disadvantaged Chinese students tested had better skills than the OECD average.

"The quality of their schools today will feed into the strength of their economies tomorrow," OECD Secretary General Angel Gurria said.

The PISA study of 600,000 students in 79 countries shines a light on the difficultly of improving education, sometimes irrespective of the resources that are dedicated to it. That appears to be particularly problematic for OECD countries that have increased spending on primary and secondary students by more than 15% in the past decade.