An open source curriculum (OSC) is an online instructional resource that can be freely used, distributed and modified. OSC is based on the open source practice of creating products or software that opens up access to source materials or codes. Applied to education, this process invites feedback and participation from developers, educators, government officials, students and parents and empowers them to exchange ideas, improve best practices and create world-class curricula. These “development” communities can form ad-hoc, within the same subject area or around a common student need, and allow for a variety of editing and workflow structures.