by Martin Carnoy and Richard Rothstein, Education Week
After digging into international test data, Martin Carnoy and Richard Rothstein argue that the scores mask an important reality.
"Some of our conclusions are obvious; some are counterintuitive or startling. Here are a few:
• A larger proportion of students in the United States is disadvantaged than in any comparison country.
• Unsurprisingly, every country has an achievement gap between its most- and least-disadvantaged students. But unexpected is that this gap is smaller in the United States than in similar postindustrial countries, and often only slightly larger than gaps in top-scoring nations.
• Creating truly representative national samples is difficult for test-makers, and errors can have big consequences.
• We should be cautious about drawing conclusions about international comparisons from any single test.
• Just as population sampling is complex, so is the choice of topics to test.