America has been sensitive for years to international comparisons suggesting its pupils are often outperformed. But optimists have downplayed the more alarming test results, arguing the US tended to keep less academic youngsters in school longer and that its school population was more diverse than other countries.
William Schmidt, the statistician who led the US portion of the Third International Mathematics and Science Study, said it had burst the myth that the top American students could hold their own anywhere. "Our best students in mathematics and science are simply not world class," he said.
President Clinton said "there was no excuse" for the results. "There is something wrong with the system and it is our generation's responsibility to fix it. You cannot blame the schoolchildren," he said.
Perhaps most damagingly, the study showed that while American schoolchildren aged about 10 scored above international averages, their performance tailed off as they progressed through the school system. Students tested in the 12th grade - the last year of school - fared the worst against their overseas contemporaries.
On the local level, poor test comparisons have galvanised states such as California to lavish extra money and attention on education, from shrinking class sizes to a demand for "back to basics" standards.
The international study results, which were carried on the front pages of most American newspapers, will help keep education at the top of the US political agenda in this year's Congress and state elections.
They are likely to fuel an argument already raging over the maths curriculum, where traditionalists have denounced the "new-new maths" that many American schools adopted to make mathematics less boring. Critics argue that progressive methods lower rigorous standards in favour of warm and fuzzy thinking over "real-life" problems.
The reaction from the Clinton Administration, however, was to stress the need for more and better-trained science teachers - only half of physics teachers, for example, specialised in the subject at college - and to plug again its calls for national testing.
While the US Government has an Education Department, it has no national ministry that defines required curriculums for its state schools, and they are mostly funded and run at the state and district level. Conservatives have ardently defended this local control against "big government" standards.
"It's now time for school officials to bite the bullet and devise the kind of rigorous and clear standards that permit you to devise rigorous and clear curricula," Sandra Feldman, president of the American Federation of Teachers, the second largest teachers' union, told the New York Times.