More than 250 national, local, and city governments, and a wide and growing range of global and local organisations are now sharing the data that they create and use in their work. Many of these organisations are keen to see the data used by the public, and the most mature services offer tools and resources to encourage learning with their open data. Further initiatives have led to innovative learning activities around the use of open data. What does Open Data offer as a material for learning and teaching? A key factor is authenticity. The data that is shared emerges from real processes occurring within important organisations. It is often data that is used in professional work that has a real impact on our lives and the world around us. A second factor is the potential personal relevance of this data to the learners. This has a strong motivational potential – learners may want to understand what is happening in their town, or how they or their class compare with others nearby or far away. They can also identify issues that require attention locally or across wider society. In one example, high school students in Italy explore data on public funding awarded to building projects around their country and collaboratively evaluate the outcomes of these projects. Engagement with open data connects learners with societal movements to encourage greater data literacy, transparency and evidence-based action.