Podcasts and Vodcasts
..hmmn sounds technical,even scary, but actually these are simply audio or video files that are made available on the Internet for download and playback using a computer or a mobile device such as an Ipod. Most podcasts have RSS capability, which can automate the download process for the user.
Here are some great easily accessible examples that I found - all ideal for a classroom.

1. Wild Animal Chronicles
Best for: Introducing your curious students to the orangutans of Borneo or the penguins of Antarctica.
Why It’s Worth It: Six-minute, jaw-dropping, well-narrated videos perfect for grades 3–8, produced by National Geographic, available for free over the Internet? Of course they’re worth it. Topics range in size from honeybees to whales, so it’s easy to find just what you need to enrich your unit.
Where to Find it: On iTunes, or here.

2. Children’s Fun Storytime
Best for: Letting someone else read aloud to the kids for a change.
Why It’s Worth It: This new audio podcast, started this past December, features dramatically intoned readings of favorite kids’ stories like The Little Engine That Could and Lewis Carroll’s Alice in Wonderland.
Where to Find it: On iTunes.

3. Sixty-Second Science
Best for: Daily blasts of entertaining, thought-provoking science news.
Why It’s Worth It: New theories on how some dinosaurs knew how to fly, how the sun sets our internal clocks, whether groundhogs can really predict the weather, and much more, all presented in a zippy radio-news format by the editors of Scientific American.
Where to Find it: On iTunes, or here.

How to make one?? Check this out -

A great library of podcast resources here