Interesting that this thread only has a couple of posts. Maybe there is some repitition.
Anyway, course design is important for ensuring clarity and Anne's suggestion of using screencasts / videos is a good one. Rather than just relying on text instruction, reinforce it with a quick video as well.
As I mentioned in another thread a forum is a very useful way on centralising help. Encourage students to post problems in the forum, rather than email you. It has a number of advantages:
- You won't answer the same questions multiple times
- Other students will see the question and answer which will often help clarify their own thinking
- It provides a clear log or record of problems / questions
- It encourages students to help each other rather than always relying on the teacher - making your workload more manageable
- It is yet another way of encouraging student interaction