There are lots of factors at play here, but it's interesting to note the student-teacher ratios the paper describes. The under-performing Chinese rural schools

There are lots of factors at play here, but it's interesting to note the student-teacher ratios the paper describes. The under-performing Chinese rural schools are at ~17, and they say that urban Chinese schools are at ~12. 17 is roughly typical student teacher ratio in US public schools, regardless of status. In the US a ratio of 12 or less is common in elite private schools. I was expecting that the CAL program they implemented was what is known as an "Inverted Classroom". It's a learning system where students view recorded (or live) lectures by master teachers as "homework", and then use classroom time with a regular teacher to practice/drill/explore what they've learned-- not unlike a college recitation session with a TA. But that was not the case in the Chinese CAL study. Instead... > In our context, however, remote learning happened in the classroom under the direct supervision of local teachers, therefore limiting distractions and procrastination.