Collaboration is a component of many forms of learning: adult learning, reflective learning, active learning, lifelong learning, etc. One method of collaborative learning that works well in an online context is problem-based learning (PBL). In problem-based learning, small groups of learners work together on a “messy” case study with more than one possible answer. The case study should be as real-to-life as possible so that students have to wrestle with complexities and multiple potential outcomes.
Problem-based learning is ideal for developing problem solving skills that can be translated to real life situations. There are four phases of the PBL method: problem development, inquiry and investigation, solution, and debriefing performance. Learners are divided into groups, usually of about 4-6 people. The group is given a scenario and must define the problem, decide what areas need to be researched, and then divide the research tasks. Self-directed learning is thus a significant part of the process. The learners then share their research results with each other and collaborate to determine the best approach to solving the problem. Reflective learning is also part of the process as students reflect on and evaluate the group learning process in the debriefing stage .
In an online classroom, the problem-based learning approach can be facilitated in a variety of ways. Each group can be given the autonomy to determine their own method(s) of meeting together and collaborating. Several tools that work well are a non-graded discussion forum for each group to use to communicate with one another about the project. Video conferencing options such as Google Meet or Zoom are useful for the initial group meeting to define the problem and assign areas of research, as well as to discuss the research and discuss a solution. Google Docs and Google Sheets are both excellent tools for groups to collaborate and share their research with one another. Any group member can add notes or links to articles to a Google Doc, which are then visible to all the other group members. If groups are expected to present the results of their work at the end, Google Docs or Google Slides both offer collaborative editing options on the final paper or presentation.
 Jerome D. Scripture (2008) Recommendations for Designing and Implementing Distributed Problem-Based Learning, The Amer. Jrnl. of Distance Education, 22:4, 207-221, DOI: 10.1080/08923640802430462.