Educators and others who follow education news are not surprised by the supposedly mediocre PISA scores, that purport to compare US students to those in other countries. As happens a lot, US students score in the middle of the pack, hardly where American exceptionalists think we should be. Others have commented that the PISA scores are a Rorschach test, in which what you see in the scores is largely a function of what you think about schools, so believing is seeing.
For example, the US reports all student scores, whereas China reports only scores from Shanghai, which is not a typical school district. When you break out Massachusetts scores, those students score near the top. School “reformers” like Arne Duncan and Michelle Rhee take the opportunity to push their failed reforms, even though none of the high scoring countries have adopted anything like their prescriptions. But there is another really important factor. Educational Researchers have known for years that poverty is a really important determinant of school success. All other things being equal, students from low socio-economic status families do not do as well in school as students from high socio-economic status families. The American economy produces vast inequalities in income, meaning that we have vast inequalities in educational attainment. There’s a really good discussion of this point on the Crooks & Liars blog. I recommend reading it.