We are studying earth science this fall and having a great time of it. We spent a week learning about the water cycle. For starters, we read this book--Did a Dinosaur Drink This Water?
It was a fun and simple explanation that worked nicely for our young age group.
Then we moved into the kitchen for our little demonstration. I gathered salt, a small pan, some measuring spoons and cups, a metal pie tin, and some tongs.
Once the water came to a nice rolling boil I used the tongs to hold the pie tin a couple inches above the pan so some rain (or condensation) could form on the bottom of the pie tin. I also pointed out the steam in the air and talked about the water vapor.
We all admired the condensation that gathered on the pie tin after a couple minutes. Then we waited for the water to all evaporate--a process of maybe ten or so minutes total. When it got down to the bottom the salt was popping out of the pan like popcorn and some awesome salt crystals formed in the pan.
Me: "Because this is so cool!"
Yep, science is fun.