This cheerful box set of all four titles in the New York Times bestselling Snowmen at Night series is the perfect gift this holiday season.   Have you ever built a snowman and discovered the next day that his grin has gotten a little crooked, or his tree-branch arms have moved? And you've wondered . . . what do snowmen do when we're not watching? Each of the four books in this bestselling series shows how snowmen come alive with jaunty rhyming text and hilarious, cozy illustrations. And each book's illustrations features hidden pictures for readers to find as they enjoy the story. The perfect way to celebrate the fifteenth anniversary of the beloved series, this box set includes unjacketed, reduced-size hardcovers of Snowmen at Night, Snowmen at Christmas, Snowmen at Work, and Snowmen All Year, plus a key to the hidden pictures in the illustrations of each book.