Warriors-Into the Wild #1 by Erin Hunter

Rusty is a kittypet (he lives in a house; eats bland cat food; has no adventures) who dreams of excitement.  One day as he ventures into the woods he encounters a breed of cat which he had no idea existed.  From the Thunderclan, these cats capture their own food and live in the elements plus defend their territory from other cat clans. Rusty realizes living like this is what he has been longing for so he leaves his pampered life and goes. . . into the wild.
Lots of excitement as trouble is brewing with the ShadowClan-cat fights, some blood and death.
Admirable characters-

Rusty who is not quick to judge and will do the right thing even if it puts him in danger

 Bluestar is the Thunderclan's fearless leader who must make tough decisions on behalf of her declining clan
Readers who enjoy the Guardians of Ga' Hoole series will love this series too.
Ms. Hunter must have spent hours observing cats and imagining how they would interact in the wild to create such a detailed story!
**At first, I found all of the characters confusing.  Ms. Hunter has provided a list of characters and to which clan they belong.
Guided Reading Level: U (5th grade)
Grade Level Equivalency: 5.2
Points to discuss/warning:  The many characters could make the reading challenging and frustrating at first; violent at times; description of fights; several cats die because other cats killed them; the "cutter" is mentioned-meaning the house cats are neutered.
For some reason our library has this book labeled "young adult"?  Maybe because of the violence.