This will probably be a confusing and stressful time for the students enrolled in your classes. Clear and frequent communication will improve the transition to a new learning format. In particular, it will be important to inform students about updates to the course site, schedule, and assessments. Sharing instructions with your students on how to use Zoom or other online tools is also useful as these may be new for them. You can use the announcement tools in Moodle and in Compass/Blackboard to communicate with students.
Be sure to check out the list of resources at CITL as well.