If you look at the YES programs that Disney offers for school groups, you will get some nice appropriate educational verbage for various things. I think if you stick with AK and EPCOT, that would be best as those have clear educational aspects.
Here is a link:
http://disneyyouthgroups.disney.go.com/wdyp/listing/listingPageRender?page=YESProgramsListingPage
While the programs have more than your average Disney trip, it can help you think in a different way about what is educational at Disney. They even have links to national standards and the appropriate "classes" the trip would benefit. (for example--liberty squares american history as tied to a civics class for example).
Things that are truly educational:
EPCOT learning about the cultures of the world by visiting 10 national pavilions with citizens of those countries. Sample activities:
Oceanography: Living Seas with Nemo
Prehistoric times: Horizons
The communicores (and whatever they are called)--they have a fire safety exhibit, savings exhibit, and I cannot remember what else--many life skills opportunities here.
Hollywood Studios: Arts and sciences: Animation (I think you can draw mickey, Film production and live shows
Animal Kindgom:
Cultures (Asia, Africa)
Life Science/Zoology: Learn about lots of animals
Magic Kingdom: IMHO the toughest to explain that would be more about patience and good citizenship with American History in Liberty Square (and Carousel of progress for how things change over time.)
ETA: I looked at the linked letter and it seeemed fine until the final paragraph. I did take a physics trip to Busch Gardens and there is no way a child is "learning" physics at a theme park without access to the physics information of the rides. They will experince it, but they won't "learn" it (unless physics expert mom or dad can enlighten them.) And the sociological aspect of crowds is nonsense.
The map information was good as I completely forgot about that. That is how my children learned maps. Just using the Disney maps and figuring it out for themselves.