Cherie Werbel's chapter on "Multimedia computing and intellectual property law: what developers and users should know" in Reisman's Multimedia Computing (SCIENCE QA76.575 .M79 1996) makes a brave attempt at summary. She concludes thus:
Multimedia technology will represent a temptation to some portion of computer users and to society at large. Some individuals will seek an outlet for creativity and unknowingly use copyrighted materials without permission... For the most part, schools may be able to hide behind the fair use doctrine... As long as non-profit organizations or individuals do not use copyrighted materials for gain, they should be protected under the fair use exception to the law.(pp 398, 399)

Just where this leaves me if I want to build instructional web pages which use brief excerpts from CDs, graphics scanned from books or downloaded from the web, snippets of streamed video and passages of text transcribed from books... who can (should, might, would) say?