Given the relative uncertainty about the meaning of fair use as applied to various situations, especially in the educational setting, various interested parties have proposed the creation of "guidelines" that attempt to interpret and apply the law to common circumstances.
These guidelines are intended to provide the minimum standards of educational fair use. There may be times when copying may exceed the guidelines, but where fair use may still apply.
Faculty: you are responsible for observing copyright law so please be familiar with these guidelines.
Brevity
Spontaneity
Cumulative Effect