Think for a moment of a TV series drama, which follows a story arc, spread over several episodes. The main character undergoes transformation as the plot progresses. The story culminates with the resolution of plot towards the end. A well-designed self-paced learning experience parallels some of these elements. The learner experiences one or more ah-ha moments as s/he moves through a series of interactions with the learning environment, completing a learning arc. Learning arcs transform the cognitive state of a learner, and concerns get resolved as learning progresses.
With that background, then, here is a definition of interactive learning arc for instructional designers who build e-learning courses. An interactive learning arc consists of multiple interactions linked together in a cohesive learning experience that is complete in itself, and can be part of a larger online course.
Have you used learning arcs as short learning nuggets all by themselves? Have you used learning arcs as branches within longer web based courses? What are your thoughts about the various ways in which learning arcs get implemented?