Your students will love having classroom book bag buddies! I have had buddies in my classroom now for 20 years and they are always a hit! Here are my current 25 buddies packed and ready for their turn. For easy management I have found it best to get them ready all at the same time, but as you build the program, simply prepare them as needed.
I generally send home two pets at a time. One for the helper and one for the caboose. You can organize it however you wish, and send home one or two at a time. I have found two to be the perfect number for me.
To start, simply find a book you love and then find a pet to match. You can usually find a pet at a thrift store, a garage sale, on amazon, or department stores (such a Kohls). I will also add an informational or nonfiction companion book if the story lends itself that way. For example if the story is Brown Bear I will include a real book about bears.
Next, make a journal! Copy the cover (add a picture that matches your pet), and then copy the inside front and back so that it will open from the top showing the next page when the page is lifted.
Now, gather a vinyl backpack. Once again these can be found in all of the places listed above. Place the pet, the book(s), the journal inside of the backpack and it is ready to send home with the first student.
Remember to introduce your class to the pet, set your rules with the pet, and build the excitement!