Best Practices for Setting Up Discussions

Ensure that there are discussion topics created for your discussion forum(s)

Forums are used to group topics into predetermined themes, course units, etc. You can only post in discussion topics. If there are no topics created for a forum, then students will not be able to participate in discussions.
Within the Discussions tool, make sure that there are topics nested under the discussion forum. If you do not see topics nested under the discussion forum(s), you must create topics.
For more information, see Create an Open Discussion Topic Available for All Users in the Course or Create a Group Discussion Topic.

The option to hide a discussion forum or topic is located on the New Forum or New Topic page (or the Edit page for existing forums and topics), in the Properties tab of the Availability section.
If you selected Hide this [topic or forum], then students are not able to see it. If a discussion forum has this setting enabled, all of the topics nested under it are also hidden.
For more information, see Set Visibility for a Discussion Forum or Topic.

Students cannot access topics that fall outside of set date restrictions. If a discussion forum has date restrictions attached, then all topics nested under it will be hidden outside of those date restrictions.
The option to set date restrictions is located on the New Forum or New Topic page (or the Edit page for existing forums and topics), in the Properties tab of the Availability section. Select the Forum is visible for a specific date range check box, then fill out your start and end dates. If you want the forum or topic to be currently visible, ensure that the End Date has not passed yet and the Start Date has already begun; if you want it to be available at a later time, set the date restrictions accordingly.
If you do not want date restrictions enabled, select [Forum/Topic] is always visible.
For more information, see Set Availability and Due Dates for a Discussion Forum or Topic

If group restrictions are enabled for the discussion forum or topic, then only students within the group selected can see the discussion.
The option to set group restrictions is located on the New Forum or New Topic page (or the Edit page for existing forums and topics), in the Restrictions tab of the Group and Section Restrictions section. Select Restrict this forum to the following groups and sections to enable group restrictions for a forum or topic.
For more information, see Restrict Multiple Forums or Topics to Specific Groups or Sections.