In recent years, evaluating the performance of educational organizations has sparked increasing interest and debate. Many expectations ride on the smooth operation of school systems. It is widely believed that countries’ social and economic well-being will depend to an ever greater extent on the quality of their citizens’ education: the emergence of the so-called “knowledge society”, the transformation of information and the media, and increasing specialization on the part of organizations all call for high skill profiles and levels of knowledge. Today’s education systems are required to be both effective and efficient, or in other words, to reach the goals set for them while making the best use of available resources. This paper, by presenting and discussing a case study, will analyze several dimensions of schools’ effectiveness and efficiency, highlighting the importance of selecting evaluation procedures that can provide representations that reflect the actual situation to the greatest possible extent.