Like any teaching method, online asynchronous discussions have drawbacks and advantages that need to be considered when creating these for your course. College professors have known for a long time that students can learn a lot in discussion with one another, especially with a moderator providing prompting and direction. Like all class discussions, online message-board conversations enable students to build a sense of community. Unlike "synchronous" discussions, whether face-to-face or via web conferencing or chat, asynchronous discussions allow students time to think before replying to your prompt, or each other. In message boards, students can be expected to practice good writing skills. Students have a record of the discussion, likely stronger than even the best of their note-taking, that they can review for further work in the class. Experts from outside the class may find it easier to participate, as they needn't attend class at a particular time (or place).

On the other hand, participants cannot make eye contact or judge the tone of other participants, so extra care is needed in composing posts. (This is not necessarily a drawback; these are skills worth cultivating in students anyhow). An instructor needs to spend extra time preparing instructions for student posts, including content, writing, and even nettiquete guidelines. Above all, with class size and discussion frequency, instructor workload can grow percipitously. In a face-to-face, classroom setting or online via web conferencing, unless you record the discussion you're forced to consider, respond to, and assess, and respond to student input "on the fly," as the discussion takes place. Because an instructor is able to spend more time with student responses in a message board, she or he might feel obligated to make enormous efforts to assess students' input.