The Space Science Institute is developing Starchitect, a stellar and planetary evolution game for Facebook. Supported by NSF and NASA, the game uses the “sporadic play” model of games such as Farmville, where players may only take actions a few times a day, but may continue playing for months. This framework is an excellent fit for teaching about the evolution of stars and planets: systems evolve in scaled real time (a million years to the minute), so that massive stars supernova within minutes, while stars like our sun live for weeks, possibly evolving life before ending their lives as white dwarfs. Simultaneously, however, the framework raises a variety of challenges relating to depth and breadth of content, conflicts between known science and gameplay, and evaluating long duration activities with finite resources. We will examine some of the challenges (and opportunities) we have encountered to date.