PISA: International Science Proficiency (adapted from BSCS, 2008)
In 2006, the Organization for Economic Cooperation and Development’s (OECD) Programme for International Student Assessment (PISA) surveyed scientific competency among more than 400,000 15-year-olds in 57 countries. Students were assigned to one of six achievement levels based on a raw score.
Figure 1.1. Science proficiency of 15-year-old students in the 30 Organisation of Economic Co-operation and Development (OECD) countries. Top: Mean scores. U.S. students rank 21st and well below the OECD average. Middle: Percentage of students scoring Level 1 or lower. U.S. students rank 27th. Bottom: Percentage of students scoring Level 5 or higher. U.S. students rank 15th at about the OECD average.
One argument put forward to explain the poor performance of U.S. students is that the United States has a relatively non-selective school system. U.S. schools must integrate all levels and abilities within a school while other countries use high-stakes tests as early as the fifth grade to track students within or between schools. However, PISA proportionally samples all students in each country and not just elite students, so "selection bias" is not a valid explanation.
It is also not the case that "the best U.S. students are the best in the world." Only 1.5% U.S. students compared to an OECD average of 1.3% reached Level 6, and the number of highly proficient U.S. students (who reached Level 5 or 6) ranked 15th among OECD countries.
It has been suggested that the performance of students in the United States is simply a function of students with dramatically differing abilities. The PISA data, however, not only compare the mean results for each country, but also the disparity between the highest and lowest performers. In some countries, not only is there a high average performance, but also a smaller gap between the highest- and lowest-performing students, while other countries, such as the United States, show lower mean performance as well as a large disparity between highest- and lowest-performing students. The fact that some countries have been able to overcome differences in innate ability and bring students to a more comparable performance level suggests that changes in education in the United States may be beneficial.
Another argument that has been made to account for the poor performance of U.S. students is that other countries have more homogeneous populations. While this may be true of some of the top-scoring countries (Finland #1 or Japan #6), this is not the case in others. Hong Kong–China placed #2 in mean scientific proficiency and percent of students scoring above basic proficiency. In China, significant proportions of the population speak different languages, while the United States has only one official language. It could be argued that many parts of Asia are as heterogeneous as the United States.