TimeWalk.org is an open source project that enables student-contributors to build historically accurate 3D models of their towns. Over the course of 9 classes, our students learn SketchUp, Github, and Unity3D. We are a 501(c)(3) nonprofit, collaborating with local libraries and schools to bring history to life. Our curriculum and supporting materials can be found on our Github page at https://github.com/TimeWalkOrg.