1. Minecraft: Popular and relevant for education With over 110M players, 241M logins per month, and 2B+ hours played on Xbox alone 1 , in 2016 the video game Minecraft ascended to be the second most popular game in history, passing Grand Theft Auto V but still well behind Tetris (Peckham, 2016). One way to think about its reach and appeal is that millions of children worldwide decide on a daily basis to interact deeply and meaningfully with a game that is essentially a simulation of the natural world. We believe it is likely that this vast amount of time spent playing Minecraft is influencing the way children think about science, technology, engineering, and math (STEM), and are engaged in a research project that explores this question. Because of its flexibility, appeal, and inherent connections to STEM learning, Minecraft has seen a dramatic rise in its adoption by educators worldwide who are using it as a platform for student projects, sharing, and learning (Schifter & Cipollone, 2013; Schwartz, 2015). Interactions in Minecraft involve a broad range of educationally relevant content (Lane & Yi, 2017): Exploring and investigating different biomes and climates that match those on Earth, including deserts, forests, jungles, taigas, and many others. Navigating in and around different types of terrain, such as hills, mountains, caverns, caves, oceans, and more. Interacting with a wide variety of wildlife and agricultural content, including animals, fish, birds, wheat, grass, fruits, vegetables, and a long list of fictional content. Searching for, mining, collecting, and combining many different resources such as different kinds of wood, stone, metal, dirt, and more. Building electrical circuits, switches, complex machines, and automated farms. Players have even reconstructed world wonders, many of which can be found online (e.g. YouTube, dedicated servers). For example, the Taj Mahal is a popular project, as are fictional places, such as Westeros from the Game of Thrones. To achieve such feats of engineering, players often work collaboratively by planning and coordinating their tasks. They assume roles (e.g., mining for resources, planning a base/fort, crafting tools and weapons, etc.), work iteratively to refine their creations, and of course, share their work with friends, family, and the online community. Thus, not only is there a need to better understand how Minecraft may frame STEM learning generally, there is also a need to provide research-based support for its use in specific contexts and educational settings. 2. Top level categories of Minecraft activities Soon after its release in 2009, educational uses of Minecraft quickly appeared online via teacher blogs, YouTube videos, and in educational technology news sites. Arguments for its appeal for STEM learning were often intuitive and compelling (Short, 2012), and its rapid adoption ultimately lead to Microsoft's release of Minecraft: Education Edition, a version of the game that comes prepackaged with tools specifically for teachers and classroom uses. 2 However, despite the success and rapid rise of Minecraft as a learning environment, very little effort has gone into formalizing its various connections to STEM. If the game continues to be popular in educational settings and we are to work towards evidence-based practices, it will be important to provide a substrate for the activities learners perform while playing. The goal of our taxonomy is to act as one possible foundation for more rigor in examining Minecraft. We seek a thorough, although certainly not comprehensive, overview of everything you can do in Minecraft.