The movie, released in 2007, is vastly different in plot, offering much more action and suspense, which works equally well. It's one of the rare instances where I've enjoyed a movie as much as the book. It can be streamed on Amazon for $2.99 (at the time of this post) or purchased on DVD for $8.99.
This story would work well in an elementary classroom as a literature circle selection, or as a read aloud. The book includes some of Crusoe's perspective, which would be a perfect springboard for a discussion on point of view.
The audio book, narrated by Nathaniel Parker (narrator of the Artemis Fowl series), is a wonderful companion to the printed book and would be a nice addition to a "listen to reading" station in readers' workshop.
"The Water Horse's" guided reading level, for those who need to pay attention to such things, comes in at a Fountas and Pinnell level Q or Lexile of 910.