So this year I made this:
Our animal classification box. There are divisions for Invertebrate/Vertebrate/Arthropod, then into the classes: mammal, bird, echinoderm, insect, etc...
Here is the control chart. I downloaded it from here.
Then there are animal picture cards 3-4 for each class. I based them off the ones available at the above website. I didn't like them so I found my own pictures and printed them on business card paper (makes it so much easier!)
Then there are reference cards that tell a few facts about each class:
We've been working through it together. So far sorted all the animals into their Phylums and the vertebrates into classes (no I didn't actually use the phylum/class terminology with them...) Tomorrow we tackle the invertebrates, before they choose which animal they want to do their reports on.