to particiapte in the PISA test.
https://isteve.blogspot.com/2011/12/pisa-what-about-rest-of-china.html
"The recent results from the international standardized PISA tests in math, reading and science will make this an increasingly untenable position. Shanghai got by far the best results out of all the OECD countries (never mind the developing ones). . Now while you might (rightly) argue Shanghai draws much of the elite of the Yangtze river delta, the Financial Times has more: “Citing further, as-yet unpublished OECD research, Mr Schleicher said: “We have actually done Pisa in 12 of the provinces in China. Even in some of the very poor areas you get performance close to the OECD average.””