It does allow you to manage the sharing of books among all the devices on the network, but not to "any number of devices." The number is "one," at a time. Don't get me wrong, Whispercast is exactly the kind of management tool that schools have been looking for for a long time and the list of capabilities (view here: https://whispercast.amazon.com/) is impressive. I think, beyond the loss of the ability to share one book to six devices, Whispercast must make it difficult or impossible to adjust settings for different situations, as Liz suggests in her post here: http://edukindle.ning.com/profiles/blogs/no-to-whispercast. Interesting read, and you can contact Liz through the site to get more info. Please share whatever you find out and decide! (p.s. love the page styling!)
Hey, Brenda! Good news on the Kindle Fires! The feeling on Whispercast is that in smaller implementations it is not worth it, since it restricts your ability to share a single copy of a book to multiple devices. If you are willing to put in a little extra effort, you can preserve the sharing to multiple device capability and still manage your Kindles successfully.