Grade 3-6-This fourth book about the Hatford brothers and the Malloy sisters begins shortly before Christmas, three months after the Malloys move to Buckman, WV. As the holiday season approaches, the boys and girls continue to play pranks on one another and begin to learn the consequences of their actions. Caroline Malloy and Wally Hatford are partners for their fourth-grade December project and discover that, instead of annoying one another, they need to learn how to work together in order to receive a passing grade. Told in their alternating viewpoints, the story moves quickly, continuing the mischief and humor of the previous novels. Readers will be especially taken with precocious and dramatic Caroline, who will stop at nothing for revenge. While it is not necessary to read the first three books, fans of the series will enjoy references to the characters' past pranks and will delight in the promise of future additions to this ongoing battle between these rivals.