4. ILSAs

In Chapter 4 we analyse in detail the findings from International Large Scale Assessments (ILSAs). We describe the magnitude of differences in different countries’ student performance, and explain the main geographical differences, as well as trends over time. Despite huge disparities between countries in terms of student performance—which generated an expectation that education systems could improve rapidly by learning good practices from top performers—according to PISA, in most countries no improvements have taken place in almost two decades. The explanation could be that governments have not adopted the right education policies, that PISA policy recommendations are wrong, or a combination of both. We closely investigate the available evidence and the conclusions drawn by PISA, and suggest that policy recommendations related to the lack of impact of investment are solid, others are strongly context-dependent, and those related to equity are not based on robust evidence and are therefore debatable.