All the attractions given in this thread are definitely very educational and I would recommend them as well...
And I think in addition to going to them, its good to have a lot of interaction with your kids about whats going on, before and after the attractions.
I reallly like what BethC1952 said about asking your child specific questions (both pre-prepared and improvised) about the park and the attractions. About how they think Disney intends on both affecting and educating people.
Also, giving your own input on each ride/attraction and tying together, helping to synthesize overall common themes of the park: like "progress" in Futureworld or Tomorrowland (or even Frontierland for that matter), or "Freedom/liberty" in Liberty Square. And explaining those themes beyond naming them.
Also, giving the kids an idea of the concepts that arent as obvious in the rides or park...or ones that kids may not immediately see a relation. And identifying and explaining the ideals/concepts that influenced or flat out led to the creation of the attractions and are very much in those attractions if people look a bit further past the obvious scripts, backgrounds, or attention getting characters of the ride.
Even better, before you offer your ideas, try to ask your child to see and discuss the common themes! Not only will they then be on their way to learning the actual educational concepts behind Disney, but its a good exercise in thinking and deductive reasoning as well! Yup, "deductive reasoning" in Disneyworld, this place has it all!!
And spend some time on Imagination with Figment...it can be quite educational and fun as well!
I love Disneyworld for many many MANY reasons, and one of those reasons is because I have a strong appreciation of what (i believe) a lot of the concepts in the park stands for, beyond just the obvious fun. Yeah, a cute purple dinosaur is (almost) always enjoyable for kids...but one that tells a kid that they can have confidence and purpose in the fun things they can come up with in their head...well that's a purple dinosaur a kid can really see as a friend and can relate to

Disneyworld can go so much further then just the fun at face value (which in itself is quite fun), and i think a lot of that deeper fun (whether it be educational, emotional, etc) is responsible for many lifelong Disney fans
