What makes PISA unique?
PISA benefits from its worldwide scope and its regularity. More than 70 countries and economies have taken part in PISA so far and the surveys, which are given every three years, allow them to track their progress in meeting key learning goals. PISA is the only international education survey to measure the knowledge and skills of 15-year-olds, an age at which students in most countries are nearing the end of their compulsory time in school.