Very exciting - my first linky party!!
The book I am suggesting is Peter Claus and the Naughty List.
I use it as part of our persuasive letter writing unit. Peter is Santa`s son and he is on the naughtly list. He feels bad for all the kids on the list so he goes about getting them on to the nice list. Since he did this nice thing he too is moved to the nice list. We use it as a jumping off point for writing a persuasive letter to Santa explaining why we should be on the nice list. Click here for the writing activity.