One of the most fun and interesting ways I have found teaching new students over the past many years is by using the basic 12-bar blues progression.
This progression is very easy to learn because it uses only three basic chords, and the sound is easily recognizeable. Most people that I have taught this to always comment "I've heard this many times before."
Not only is this progression easy to learn, but it is also easy to teach.
The best part about the blues is that you can do a ton of things with it to make it sound very interesting while still being very easy to play.
I have put together a podcast in a series of podcasts entitled "Piano Lessons: Basic Blues in the Key of C" that teaches you this progression.
To access this podcast
To access this podcast through PodcastAlley.com
To access through Odeo.com
My Odeo Channel (odeo/a899ff8db4f63f39)
To access this directly through iTunes