This design-based research (DBR) study had both local and general goals. Its local goal was to increase active learning in the online courses offered at a large research university in the midwestern United States. Its larger goal was to define active learning design principles for online courses in general, so that they might be used to improve the learning experience for wider audiences. While the principles of active learning can be applied to courses in any mode of delivery: flipped classroom, blended, or fully online, the importance of active learning in online courses is highlighted because active learning course design requires numerous upfront considerations. Moreover, because the pedagogical model is structured throughout the online learning environment and thus is made visible, online courses present a unique opportunity to review what is core to the principles of active learning. The design intervention (an innovative course review method) incorporated the principles of authentic e-learning. The study addressed two major research questions: (1) "To what extent does the intervention--a new course review method--indicate the extent to which active learning is present in the design of an online course?" and (2) "How do the principles of authentic e-learning incorporated in the new course review method need to be refined?" To address the first question, the online course review intervention was used to evaluate the learning activities and assessments of 75 undergraduate online courses against these authentic e-learning principles, resulting in an active learning (AL) score for each course. To address the second question, we surveyed the learners in these 75 courses about what made learning meaningful and coded the learners' feedback in reference to the active learning design principles. The practical outcome of this DBR study is a pedagogical course review that quantifies active learning in online courses. The theoretical outcomes of this DBR study are refined active learning design principles that can serve instructors, designers, teacher educators, and administrators in enhancing the design of online courses. The findings of this study affirm that the authentic task principles as well as newly identified learner-centered design principles together can serve as evidence-based principles to define and refine active learning in online courses.