I have used short segments of the Mechanical Universe Programs, providing my
own discussion and asking for interaction from the students. I have found
many of the animation sequences and some of the historical bits useful, but
_never_ have I shown an entire program to a class. It works well as an
animated chalkboard and 45 second to two-minute supplements with frequent
use of the fast-forward, rewind, and pause buttons. Programmable remote
controls are really helpful in using these videos this way.