From Webkinz Insider Wiki
This is a work in progress. Lots of details still need to be filled in.
Overview of Webkinz CaresWebkinz Foundation Website
- "This campaign launched in June 2008 in Walgreens stores across the United States. Selected classic Lil' Kinz® pets now carry an additional red ‘Webkinz Cares’ tag. A portion of the sale of every specially marked Lil' Kinz pet goes to the Webkinz Foundation™. These ‘Webkinz Cares’ pets offer an exclusive feature code as an extra-special thank you to members who support our Foundation." 
Webkinz Cares Pets (also sometimes called "wCares Pets") are identical to regular Lil' Kinz Pets in every way with the exception of the extra red tag and feature code which unlock additional gifts and prizes.
If you already have a Webkinz World account, you only need to enter the code found on the Red Tag to access to the Webkinz Cares features. It's the code on the special red tag that gets players access to Webkinz Cares features, not the adoption code on the blue tag. You do not need to enter the pet's adoption code (on the blue tag) until you're ready to adopt that pet.
- More information at Webkinz Newz
Webkinz Cares Prizes
List of Webkinz Cares Pets
This is an alphabetical list of Webkinz Cares Pets. For additional information on the pets listed below, please see the Full List Of All Webkinz Pets.