Alan November, respected educational technology consultant, offers a free online tutorial for teachers. From the November Learning, December 2007 newsletter:
In this month's featured article, learn how to help your students publish, produce and direct a movie library of meaningful content-rich tutorials. Screencasting is a powerful teaching tool. You can record a movie of what you are doing on your computer complete with voice-over instruction. Screencasting can be used with any computer application and in any subject area.