She's *probably* a little young, but keep the BBC's Walking With ________ (dinosaurs, prehistoric beasts, etc.) in mind. *Amazing* animation.
Aside from what you've already listed (great ones!):
- Bill Nye the Science Guy
- National Geographic (anything by them)
- H's The Universe
- Carl Sagan : Cosmos
And about 1,000 out of 10,000 other titles in Netflix Streaming : Documentaries : Nature & Science documentaries.
Don't forget the computer, however!!! 3ish is the PERFECT age for www.starfall.com & iSpy
As far as semi-edu (social/emotional instead of intellectual) videos my favorites are the calmer/ more subtle british titles, they're *great* for quiet time:
- Kipper the Dog
- Thomas the Tank Engine
- Angelina Ballerina
- Fireman Sam
- (or the more boisterous) Bob the Builder
Sprout has some of these :P, but they hop around like crazy and do all sorts of "bounce around" schtuff in between them (not great for quiet time), nor for long attentions. We just got them on DVD. My son split his tv time about 1/2 & 1/2 between Dr Neil deGrasseTyson / Carl Sagan/ et al & Thomas/Kipper.