The original episodes of The Mechanical Universe once streamed from the Annenberg Learner website and were available for purchase there. That changed and it seemed like they would be lost forever. But then CalTech posted them, so it seems all is well.
But the High School Adaptations followed a different path. They were available for purchase for years (VHS and then DVD) from Intelecom. But any and all distribution ceased years ago, and these pared down and reworked videos seem to have been lost to the mists of history. You cannot buy them and you cannot stream them.
So I decided to post them as "unlisted" videos on my YouTube channel. Two copyright claims popped up when I uploaded them. In "Introduction to Waves," someone owns the license to The Marriage of Figaro music that plays in the episode, so that episode is subject to ads that would benefit the license holder. In "Navigating in Space," a minute or so of Voyager Grand Tour animation is owned by the BBC. Inclusion of that minute would block the video from running, so I removed the offending content and tried again. No block; no strike!
Links to all 28 High School Adaptation episodes can be found at the bottom of this page:
The Mechanical Universe of Phyz
And now that they stream, they make for nice YouTube homework assignments! This frees up classroom time for other activities.
I feel awkward posting these videos since they don't really belong to me. I have not been asked by any license-holding stakeholder to cease or desist. At this point, they may be covered by Fair Use. I honestly don't know. It is certainly not my intent to infringe on anyone's copyright.
Here's an old favorite:
The Law of Inertia