The latest international test results were released this morning, and the U.S. is getting favorable early coverage for scoring anywhere between the top 3rd and the top 6th of the pack, depending on the subject and the grade. But many poor nations participate in TIMSS (the Trends in International Mathematics and Science Study) giving an inflated impression of how well we actually perform compared to our economic peers.

The picture changes when we consider only those nations that are among the top-30 in terms of gross national income per capita. Limited to those nations, the U.S. places 6th out of 11 at the 8th grade in both mathematics and science. At the 4th grade, we place 7th out of 16 and 6th out of 14 in math and science, respectively. That is despite the fact that we spend more per pupil than every country that outperforms us, and indeed more than any of the 48 participating countries except Norway.

The U.S. is also getting plaudits for rising TIMSS math scores since 2003, though our performance in science seems to have stagnated. It is inevitable that advocates of the No Child Left Behind law will claim credit for the math gains, but let’s not be too hasty in going along. First of all, the PISA international test results released last year show declines in both mathematics and science scores since 2003, and the math decline is statistically significant. So TIMSS is not the only word on the issue. Moreover, the 8th grade gains in student scores that occurred on TIMSS between the late nineties and 2003 — before NCLB could have had an effect — are larger than those that have occurred since (4th grade TIMSS scores are not available for 1999). The same pattern is true of America’s own National Assessment of Educational Progress.

So we’ve thrown $100 billion or so at NCLB and, at best, performance has improved more slowly than before the law was passed. At worst, it has declined. The Obama administration should give these facts serious consideration in deciding what to do with the law.