Our first lesson was actually the introduction to explain how history is learned. Through stories, written or otherwise, and from finding artifacts buried over time discovered by archeologists. Each piece or letter helps put together the puzzle of the story of the world for its time.
A suggested activity to discover what it is like to dig up artifacts and try to figure out the story of a lost world was to create an archeological dig in the yard, all taped off just like they are 'for real'.
I decided a more simple route for our purposes. I collected artifacts from the long lost civilization of "Barbie and Polly" and buried them in different layers in a disposable aluminum pan in corn meal and corn flour. Wetting areas created a thick, rocky clay to dig through. Using baby spoons, paintbrushes, and some play dough tools my girls got to work unearthing the treasures.
We had a wonderful time piecing together the story of the dolly world. I threw in a couple of unknown elements so my kids learned that sometimes archeologists have to talk to each other and look to other resources to discover what things are.
And yes, even the toddler got in on the action!