I'm curious whether the students in Hong Kong who were tested were already top performing students, or at least average or above, because the low-level kids were filtered out and tracked to non-academic career pathways. In the US, the scores reflect all the kids, even the ones who come from low SES and have low cognitive ability. So in Hong Kong, and similar high-performing countries, who is being tested?
Another factor is there's a culture of hyperventilating over test scores in Hong Kong, like in much of SE Asia. A 98% is not to be celebrated, it's a family crisis.
