Here is what I have learned so far......
Transferring an item to another format (example: video to DVD, film to video) is never acceptable EXCEPT:
-the medium on which the work is stored is obsolete (based on the legal definition of "obsolete")
-the item is not available for purchase in a newer medium.
So, let's say a school has a video of The Magic School Bus Inside a Beehive, for example, and they would like to replace it with a DVD. They may not copy the video into a DVD format since the item is available for purchase on Amazon in a DVD format.
Obsolete means the machine that plays it is no longer manufactured or reasonably available in the commercial marketplace. VCRs, although scarce, are still around and still available. I am surprised by how many students at my school still check out videos (but mostly when the DVD of the item is checked out.) Transferring cassettes to CD would also be unacceptable since cassette players are not obsolete.
More on this later...
Simpson, C. (2005). Copyright For Schools: A Practical Guide. 4th Edition (p. 78). Worthington, OH: Linwoth Publishing, Inc.