Communication
I find responding to students questions early as possible has been very effective.
I would think this is true. Students tend to give up from feeling isolated in the course. If they are contacted in a timely fashion they are more likely to continue on.
I agree with everyone as well, timely fashion not only puts the students at ease in knowing the instructor is there for a quick response, but it also helps them progress with the course quicker because they are not waiting a long time for a response from the instructor on a question they may need resolution for in order to go forward. My turn around time is with 24 hours via email. But during my office hours I have various ways of contact for instant gratification.
