This case study of a teacher who engaged his students in inquiry within a technologically rich classroom was conducted over 5 weeks, including 15 regularly scheduled classes. Data include extensive teacher interviews, e-mail, and artifacts such as class notes, curriculum guides, and handouts. A retrospective analysis methodology was utilized to address what Barron et al. (1998), called the "major hurdles" in implementing project-based curricula: the simultaneous changes in curriculum, instruction, and assessment practices. In addition, a framework developed by the National Research Council's " How People Learn" was employed to provide detail on the nature of knowledge, learner, assessment, and community centeredness of the project-based unit. Finally, the classroom environment created during a unit of astronomy was analyzed and five principles emerged: the sense of a project, the development of independent individuals, creation of a global community of learners, a cyclic nature of instruction emphasizing conceptual and procedural understanding, and the utilization of distributed expertise.