How can school performance be measured accurately to improve learning outcomes? "Measuring Improvements in Learning Outcomes” proposes a value-added model of measuring which provides a more fair, precise and quantitative tool for assessing students’ progress. Unlike some league tables which rely on raw test scores, value-added modelling measures what students have learnt while in school by monitoring their performance at two or more points in time. It also overcomes many of the problems plaguing other models which can be biased against schools with socio-economically disadvantaged students. The report sets out three broad objectives for using value-added modelling: - school improvement initiatives, to better develop specific programmes. - school accountability, to enable fairer and more accurate evaluations of performance to ensure resources are being used efficiently. - school choice, by providing parents and families with information on the performance of different schools. The cost of education in OECD countries rose by an average of 39 per cent between 1995 and 2004. If outcomes are to improve, accurate measures of performance are essential. This OECD report emphasises the benefits of using value-added modelling and, importantly for policymakers, discusses a number of implementation strategies available to governments. This report is divided into three parts: Part I: Objectives and use of value-added modelling, including examples from schools in the United Kingdom, the Netherlands and the USA. Part II: Technical aspects of value added modelling, with comparative tables from OECD countries. Part III: Implementation of value added modelling, providing guidance for policy makers and administrations on how to implement a system that best meets their needs.