Is it a violation of copyright laws for educators to allow students to photocopy an entire book if the book is out of print and can't be disseminated any other way?

Yes..... probably.

Photocopying 'parts' of copyrighted material for educational purposes is normally OK, but if you want to copy 'large' amounts or an entire work, then this is not allowed without permission or on expiry of copyright.
Some work, usually intended specifically for educational purposes, does include a section about copyright and allows reproduction... but this is very rare.

Thanks, Adi.