Global warming and climate change create a compelling context for evaluating existing building stock. Buildings use almost 39 percent of global energy, and they produce an estimated 30 percent of greenhouse gas emissions. Actions on one-structure-at-a-time are insufficient; meaningful solutions must impact multiple buildings’ energy use. In ‘Pervasive Games’ for architecture, real-world locations are gameboards; architecture is the context and the subject of players’ actions, and its improved functionality is the game objective. ‘Pervasive Games’ have the potential to prompt individual, group, and community action, expanding the space, time, and social circle of game life into ordinary life and vice versa. They can give meaning to ordinary life action in digital and physical game spaces, directing play meaningfully to energy-reduction goals in ‘Pervasive Energy Games’. The efargo ‘K-12 Challenge, a Pervasive Energy Game’, implemented in some Fargo-area K-12 schools, empowered students to make school buildings into game spaces, with the dual goals of achieving energy savings and fostering energy-saving behavior and learning.