DVDs

I recently purchased a copy of a DVD at the request of a professor. I believe that the professor intends to show this film in class.

If a teacher teaches a novel in school, can they show the DVD of the movie under fair use?

I've had an interesting question posed to me by two Social Studies teachers and... I have a feeling this may be a more pervasive issue.

We recently purchased equipment that is capable of converting VHS tapes to DVDs that will be used by staff and patrons.