China's results in international education tests - which have never been published - are "remarkable", says Andreas Schleicher, responsible for the highly-influential Pisa tests.
These tests, held every three years by the Organisation for Economic Co-operation and Development, measure pupils' skills in reading, numeracy and science.
Pisa tests - the Programme for International Student Assessment - have become the leading international benchmark.
The findings indicate that China has an education system that is overtaking many Western countries.
While there has been intense interest in China's economic and political development, this provides the most significant insight into how it is teaching the next generation.