One question is often risen in response to international 【M1】______ test comparisons: Do these results really mean anything? In the past, international testing programs have been criticized on variety of grounds. Two allegations, in particular, have 【M2】______ been common: first, that other nations have not tested as large a percentage of their student population, and nevertheless their【M3】______ scores have been inflated; and second, that our best students are among the world's best, with our average brought down by a 【M4】______ large cohort of low-achievers. Whatever the historic validity of such concerns, they are 【M5】______ now, if anything, reverseD.Particularly in the fourth and eighth grade, education has become universal in all of the leading nations. Therefore, in science, the percentage of randomly selected【M6】______ U.S. schools and students that actually did participate at the eighth grade level was just 73 percent—the third-lowest of all 45 participating countries, and 11 percentage points under the【M7】______ average participation rate of industrialized nations. In fact, the United States had third-lowest overall participation rate for both【M8】______ grades in both subjects. Japan, Taiwan and Singapore all had participation percentages in the 90s. How about our best and brightest? At the fourth-grade level, there is some real truth to the idea that the best American students【M9】______ are among the best in the worlD.Looking only at the top 5 percent of test-takers, American fourth-graders beat the average of wealthy nations by 13 percentage points. By the eighth grade, however, the tables have turned, with America's brightest students fallen 10【M10】______ percentage points behind their foreign peers. 【M1】