Forums are moderated by teaching staff and instructors can post comments in forums as well. While students can post content within forums, they cannot create forums themselves.
TA's help in the Instructor in creating forums as well as responding to students queries. Some tips while monitoring forums:
• Monitor discussion forums for bugs and emergencies and report these to course staff as quickly as possible.
• Seek out the best discussions, most interesting questions, and highest voted posts and surface these for professors and staff to respond to as desired.
• If you can, directly explain concepts, answer student questions, and clarify course logistics in the forums
• Flag abuse and Honor Code violations.
• Its also good to collect student feedback's and questions and create a course wiki.
For more information please refer to this link