|In the physical classroom, peer interactions motivate students and expand their perspective. We suggest that synchronous peer interaction can benefit massive online courses as well. Talkabout organizes students into video discussion groups and allows instructors to determine group composition and discussion content. Using Talkabout, students pick a discussion time that suits their schedule. The system groups the students into small video discussions based on instructor preferences such as gender or geographic balance. To date, 2,474 students in five massive online courses have used Talkabout to discuss topics ranging from prejudice to organizational theory. Talkabout discussions are diverse: in one course, the median six-person discussion group had students from four different countries. Students enjoyed discussing in these diverse groups: the average student participated for 66 minutes, twice the course re- quirement. Students in more geographically distributed groups also scored higher on the final, suggesting that dis- tributed discussions have educational value.