Results on standardized tests are becoming a common way to evaluate student performance in different school systems, such as in different states of the United States. These tests are especially important in international comparisons of student performance since school systems differ so much across countries. International tests in mathematics, science, and reading have been given to high school students in different countries every few years since about 50 years ago. The well-know PISA tests started in 2000, and the number of countries included has been expanded by 2009 to over 60.
Scores on standardized tests have many well-discussed problems from the viewpoint of measuring how much students learn. For example, teachers may concentrate on materials that are likely to be on a test rather than on other possibly more important knowledge- this is called “teaching to the test”. Still, standardized tests are a much better way to compare achievements among students, and especially among students in different countries, than are various measures of average years of schooling- the most commonly used measures in international comparisons.
The US spends much more per student than any other country (with a few small exceptions). Yet from the very beginning, American students have generally performed below average compared to students from the richer countries that comprise the OECD countries. In 2009, the average American student did a little better on the PISA tests: they were much above students from the great majority of the 65 countries that participated, and were at, but no better than, the average level of OECD countries.
Another interesting case is that of Chile. Some critics have used Chile’s below average performance on the PISA tests to oppose Chile’s extensive use of school vouchers. Chile’s performance may be disappointing, but in 2009 Chile did the best of all Latin American countries (Chile was a little behind Uruguay in math), and much better than Brazil, Argentina, and Mexico (except again in math where Chile did about the same as Mexico), even though Argentina has a much longer tradition of emphasizing education.
Japan and other Asian countries typically place much greater emphasis on rote learning and memorization than does the United States and some European nations. South Korea, Japan, and Hong Kong rank high on the PISA tests, much higher than the US. However, America is the world leader in game-changing creativity and innovations, far above these other countries. Perhaps America’s lead is related in part to the emphasis that the American education system places on creative thinking rather than memorizing what famous people have said.
Russia provides another interesting example. Russia has produced many outstanding mathematicians and scientists, yet the Russian Federation ranks quite low on the PISA tests in mathematics and science.
Modern economies have enormous specialization by skill, type of industry, and various other characteristics. This implies that an economy can perform at a high level even though not everyone is well educated in mathematics, science, reading, or other fields. It is sufficient if enough young persons are prepared in these subjects to supply enough trained men and women for the jobs and other tasks that require specialized training. Such specialization implies that not only are the average scores for different countries relevant, but so too are measures of the distribution of scores among students within a country. Calculations by William Hubbard of the University of Chicago Law School for the 2003 PISA results do show that the US ranks somewhat higher relative to other countries when comparing the variances in scores among students in the same country than when comparing average scores.
That the distribution of scores is important does not deny that average scores may also matter a lot in modern economies that rely extensively on the labor force’s command of knowledge and information. to test this hypothesis, a few economists have related average scores on various international tests in math and science, along with average years of schooling and other variables, to subsequent growth in per capita incomes. Eric Hanushek of the Hoover Institution pioneered this approach, but the latest study I know of is by Appleton, Atherton, and Bleaney, “International Test Scores and Economic Growth”. They show that higher scores by different countries are followed in later years by moderately higher growth rates in GDP, holding constant initial per capita incomes, average years of schooling, and some other variables. Test scores are far more important than average years of schooling in predicting subsequent economic growth.
International comparisons are always somewhat suspect because differences across countries that are not observed by economists rather than the variables that are measured may be producing the results found. For this reasons, Appleton, Atherton, and Bleaney also relate changes over time in test scores within countries to subsequent changes in their economic growth rates. They find much weaker results in these within-country comparisons, which is not uncommon.
Despite all the qualifications, scores on standardized tests, like the PISA tests, are much more effective ways to compare student achievements in different countries than are average years of schooling and other measures of school years completed. As I indicated earlier, the mediocre performance of the average American student on the PISA and other tests may indicate only that the US school system emphasizes creativity and independent. However, I strongly believe that it is also evidence of the mediocre performance of many American schools. International test scores have been used for decades to push for improvements in the schools available to the lower third of American students through the spread of charter schools, school vouchers, and stronger incentive to teachers, students, and parents. The 2009 PISA test results indicate that some progress is being made in American schools, but considerable room for improvement still remains.