This report explores the educational performance and attitudes of males and females during childhood and adolescence. It opens with a general summary of gender differences measured outside of the PISA assessment programme and then considers the knowledge gained about gender-related issues from PISA 2000, PISA 2003 and PISA 2006 when reading, mathematics and science respectively were the major domains of assessment. Among the key findings: in reading in PISA 2000, females significantly outscored males in all countries; in mathematics in PISA 2003, males outscored females somewhat; in the combined science scale in PISA 2006, there was no overall significant difference observed between males and females. However, when examining the various science competencies, knowledge components and attitudes to science, there were some marked differences.