In an online environment, instructors can go beyond the traditional use of textbooks and incorporate other resources and materials including videos, articles, and web links...just to name a few! Varying the presentation method in an online course is just as critical as in a face-to-face environment.
As part of active learning, students need to demonstrate that they understand what they have experienced. Letting online learners create a wiki or post a on a discussion forum, allows them to practice what they learned.
The key word in designing an online class or lesson is "engagement." How do we keep students actively learning? Creating learning activities that promote interaction is imperative.