I went to Sheridan College back when the only other animation school in the world was Cal Arts. Toronto Metro region's city of Oakville's Sheridan is where all my teachers shared their professional experience and knowledge, and most if not all had worked at Nelvana, the largest (corporate) animation studio in Toronto for a loooong time (perhaps still).
Today YouTube recommended an old one, from this YouTube channel Retro Rerun, that many of my teachers worked on, plus another of that era, and I looked up the third. I actually watched all these as a kid before I even knew I'd even become an animator.
A Cosmic Christmas (23:41)
~ Retro Rerun 2019-12-05
The Devil and Daniel Mouse (~25m)
(I expect this one will arrive on Retro Rerun eventually too.)
This documentary presents the classical animation process I learned, before delving into computer animation, and back then computers didn't exist:
How We Made The Devil and Daniel Mouse (21:40)
~ Musta Costa Fortune, 2015-07-16
Rock & Rule (1:18:16)
~ Retro Rerun 2019-11-30
The Star Wars Christmas Special animated sections were also animated at Nelvana.
Many of my classmates and friends ended up at Nelvana. I consider myself fortunate to have stayed in smaller boutique studios focused on commercials with higher-end animation in Toronto and NY, then SF and Vancouver.
I know nothing more about the other content on Retro Rerun, but it reminds me of the only other great thing to come out of Nelavana (that I'm aware of): Clone High, well worth watching, even as an adult.