When you say iTunes, most people think of music, iPods, and the online store - but have you considered the uses of iTunes for teaching and learning?
As with all iLife applications, iTunes integrates seamlessly with all the other applications. So you can:
Create songs in Garageband and place them in iTunes
Create podcasts in Garageband and put them in iTunes
Use an iTunes song in a iPhoto slideshow
Use iTunes audio in your iMovie
The online store now carries a wealth of educational resources:
Podcasts are available that teach everything from French to grammar to science.