Since 1997, OECD governments have collaborated to monitor the outcomes of education in terms of student performance on a regular basis and within an internationally agreed common framework. The first PISA assessment, carried out in 2000, revealed wide differences in the extent to which countries succeed in equipping young adults with knowledge and skills in reading, mathematics and science. For some countries, the results were disappointing, showing that their 15-year-olds’ performance lagged considerably behind that of other countries (and perhaps their own expectations) sometimes by the equivalent of several years of schooling1 and in certain cases despite high investments in education. PISA 2000 also highlighted significant variation in the performance of schools and raised concerns about equity in the distribution of learning opportunities. Among the 25 OECD countries for which performance can be compared between 2000 and 2003, average mathematics performance increased in one of the two content areas measured in both surveys. For the other mathematical content area, as well as for science and reading, average performance among ...