So ever since Chloe picked out the human body model from the bookstore, we've been studying the digestive system in depth. (Love how topics come about naturally from her own interests!)
Yesterday was the stomach, how food enters the stomach and the acid breaks down the protein and calcium and the rest of it makes it's way to the small intestine.
We did an "experiment" - more of a hand-on illustration actually, but effective. We poured half a small glass of milk. The glass was the stomach, the milk was... well, milk, and we used vinegar as the stomach acid. I let her pour some vinegar in on top of the milk and we got to watch it curdle - process the protein and calcium from the milk.
Okay, so I gagged. I'm not a big fan of milk, and watching it curdle wasn't a pleasant experience for me. But it really was a pretty neat way to see acid at work in a way she could relate to it.