"TIMSS, conducted every four years, is an assessment of fourth- and eighth-graders in mathematics and science. TIMSS first collected data in 1995, and then again from eighth-graders in 1999. With the 2003 data collection, TIMSS offers the first international trend comparisons in mathematics and science at grades four and eight."
A brief summary of the findings:
"No measurable changes were detected in the average mathematics and science scores of U.S. fourth-graders between 1995 and 2003. Moreover, the available data suggest that the performance of U.S. fourth-graders in both mathematics and science was lower in 2003 than in 1995 relative to the 14 other countries that also participated in both studies.
U.S. eighth-graders improved their average mathematics and science performances in 2003 compared to 1995. The growth in achievement occurred primarily between 1995 and 1999 in mathematics, and between 1999 and 2003 in science. Moreover, the available data suggest that the performance of U.S. eighth-graders in both mathematics and science was higher in 2003 than it was in 1995 relative to the 21 other countries that participated in the studies."
You can view the full report (Acrobat PDF), OR click here for a summary of the findings.