First, we read this great book about owls:
All About Owls by Jim Arnosky is a great introductory book about owls. It gives clear, concise information about owls. The illustrations are engaging and accurate. It's written so that it appealed to all my kids -- ages 3 to 12 (and I enjoyed it, too).
After reading the book, we had a great discussion about owls we've seen and heard around our homestead and in the area before getting to the really good stuff! The three oldest boys dissected owl pellets.
This is what Josiah's owl pellet looked like when he first began to carefully peel away the fur, feathers, and vegetable matter: