I am teaching am The Great Gatsby online to high school students. Can you say CHALLENGE.
One thing that has helped is Screencast-O-Matic. (http://www.screencastomatic.com)
Here is the one that I created:
They are really easy to create:
1. Create a PowerPoint, Keynote, Word Document, Excel, etc.
2. Go to www.screencastomatic.com
3. Press the blue record button.
4. Drag the box with the dotted lines over your document.
5. Resize the box as necessary.
6. Press record