The U.S. scores are interesting. On page 28, look at the column that says "Share of top performers" (in science, reading or mathematics): https://www.oecd.org/content/dam/oecd/en/publications/report....

The U.S. is at 17.8% top performers, well behind Japan and Korea but around the same as Canada and Switzerland. But the U.S. is significantly ahead of the big EU countries: Germany is at 14%, France is at 9.8%, Italy is at 10.1% and Spain is at 7%.