OK - this is out of chronological order - but this was so fun that it deserved a posting.
Garrett and I went along with a friend's homeschooling group on a field trip to Dig It! - A Fossil Workshop. Check out: http://www.digitfossils.com/
It's a place where kids can learn about fossils and then prepare and take home authentic fossils that are millions of years old (we checked because we wanted to make sure they weren't recreations). We chose to take home obsidian, amethyst (they have a mineral pit for digging too), and a fish fossil.
We also played with dinosaurs with our friend Kien - what more could you ask for???