Disney's Animation Research Library is a marvel. It houses tens of millions of artworks from all of the companie's animated films. Story sketches, layouts, animation drawings, background paintings, models and much more.
When I started at the studio in 1980 this massive collection was housed in the basement of the Ink & Paint building on the Burbank studio lot. At that time it was called the Morgue. A few years later all the art was moved to a state of the art, temperature and humidity controlled site nearby.
As an animator I had the privilege to visit the ARL frequently and study scenes (the actual drawings) from Snow White to The Rescuers. Classic short films as well.
It was important that before each visit I sort of knew what I was interested in researching. Without a clear idea in mind your brain would drown in this seemingly endless archive of masterpieces.
Analyzing the work by Disney's incredible animators was simply the best school you could ask for. And then to have the opportunity to ask Frank, Ollie, Milt, Marc and Eric in person why they did things a certain way!
You can find "mini tours" of the Are on youtube. here is one of them: