A BIOGRAPHY OF AMERICA Annenberg/CPB
The 'companion site to the video series and telecourse'. Twenty-six chapters, each with some sort of interactive feature, including....

Some excellent maps:
- Slave and Free Soil Animated map reminds us that all 13 colonies once had slavery. (Wish: click on states to learn more).
- Mapping Conquest 8 maps in one. Nice overlay/comparison feature. Their method of turning on and off map features should be noted.
- Transportation Revolution Roads, canals, railroads to 1830-1870.
- The New West Less history than commentary, this map still has some interesting things--like the map of public lands.

Timelines:
- 1555-1735: Colonial Settlement Note that you can view events in Europe, and also other settlement activity.
- 1555-1876: America at the Centennial "Alternative timeline"; lets you view events dealing with women, African Americans, labor, and Indians.
- 1876-1999

You can find all the features at the sitemap. While the "You Decide" features don't use new media, they're an excellent example of deep interactive learning.