Before starting a class discussion, consider effective ways to introduce it to your students.

Provide Clear Instructions 
Regardless of the setting or approach adopted, it is helpful to provide clear instructions for students. For example, rather than a general prompt such as “discuss the video with the person seated next to you,” a more specific suggestion, such as “share what you found most important and most puzzling in the segment we just viewed," tends to be more effective. Let students know how much time they will have for discussion, and if/how they will be asked to share what they discussed. Provide opportunities for students to let you know how the small-group discussion strategies you have tried so far are working for them—for example, through an early course survey questionnaire or a brief reflection assignment. Not all students will appreciate the opportunity for discussion within a large class, but if they hear from the instructor that most students have expressed appreciation for what discussion brings to the class, they may feel more open to giving it a try.

Explain the Purpose
Students are unlikely to invest in discussions if they do not feel they are a good use of class time. Share your reasons for incorporating discussion and your other primary teaching techniques at the beginning of the semester, explaining to students how discussion can help them understand key concepts. When students understand why they are being asked to try something that feels a little uncomfortable, they are more likely to be motivated to participate. Try to revisit the rationale for discussion and the specific objectives of particular exercises on a regular basis.

Choose Discussion Strategies to Engage Students
Classroom discussion can include hundreds of students, a group of four or five, a pair, and endless configurations in between. Techniques and forms for discussion may be more effective in one setting and less effective in another. Here are a variety of commonly used techniques for structuring class discussion, from very simple to more complex.

• Interactive lecturing. Many instructors pose questions to the whole class as they lecture. Of course, the questions that are posed significantly influence the benefits of this approach! When planning the day’s lesson, consider what questions will best direct students to explore the areas of inquiry most essential to that lesson. Open-ended questions can provide opportunities for students to process and dig deeper into the material in lecture. Alternating 10-15 minutes of lecture with 3-5 minutes of inquiry also helps keep students engaged. 
• Socratic method. This term is usually used to refer to an iterative form of questioning that invites students to explore the reasoning behind their responses and to "dig deeper" into the topic under discussion. Selecting the questions you will ask is a key component of advance planning for class discussions. For more about Socratic teaching see this summary from the Foundation for Critical Thinking. For suggestions about question types and some specific examples, see the Harvard Bok Center's Typology of Questions.
• ​Think-Pair-Share. Many students report they feel more comfortable sharing their ideas in a small group than with the class as a whole. Think-pair-share is a technique designed to help these students become more comfortable sharing their responses by providing time first for each to THINK through their response and then share it in a PAIR, usually with a student seated close by, before being ask to SHARE with a larger group.
• Small groups. In addition to helping reticent students feel more comfortable sharing ideas in class, small groups offer students opportunities to get to know one another, learn from each other, and deepen their understanding by explaining concepts to others. Developing personal relationships in class can support student learning. Providing structure and clear directions for group work assignments helps students stay focused and understand the purpose of the exercise. ​
• Jigsaw: The "jigsaw" approach is a variation on small group work and typically requires most or all of a class period to complete. Students are assign one "piece" of a "puzzle" in which to become group "experts." They discuss their assigned topic with others who have the same assignment and plan a strategy for teaching about it. Then, students are re-grouped so that each group contains one representative for each "piece" of the jigsaw puzzle and they teach the others about their assignment segment. A final step at the college level often is completing a task that requires synthesis or application of all the pieces, once each student has shared about their portion. For more information see the Jigsaw Classroom.