Did you know iTunes offers a K-12 resource section for teachers, parents, and students? Ready for the best part? Most of the things offered in this section are free! This is part of iTunes University or "iTunes U."
iTunes U has a large variety of podcasts available for download. One of the things I stumbeled across in my search was "Ask a Biologist," a program from ASU's Life and Sciences department. The podcasts episodes revolve around interviews with a scientist and his work in the life science field. Another interesting find was from Utah State. They actually have language lessons for the Navajo language. Montclair Public Schools in New Jersey has an entire section on various literature studies.
How do you access iTunes U?
Once in iTunes, click on the iTunes Store link on the left side of the screen. Then, click on iTunes U in the top left corner of the screen. This will take you to the main iTunes U page. Under the Find Education Providers about midway down the page on the left side, click the K-12 button. This will take you to the listing for all schools participating in this program. Happy hunting!