You can change the visibility of the announcements in Blackboard so that different messages can be shown to students in their dashboard when they log in.
To organise the announcements in your module select Module Tools from the Course Management menu and click on Announcements.
This screen will display all of the announcements you have created for this module.
Only announcements below “New announcements appear below this line” will show up on the dashboard page for instructors and students under “Announcements”. If announcements are above this line they will be only visible in the full announcements area and not on the Announcement block in the dashboard.
In the example below, the announcement "Assignment is now live" will only appear in this full announcements area, the announcement "Change of room for Tuesday's class" will appear in the announcements block of the dashboard.
If you move your mouse over the left-hand side of an announcement, you can drag it up or down, to move it above or below this line.
In the example below, both announcements will only appear in this full announcements area, not in the announcements block of the dashboard.