Why just lift a flap to count down the days of Advent when you can have kids color a "mystery" puzzle piece each day of the season, then cut and re-assemble the pieces to create a beautiful Christmas scene craft?
Students can easily follow the color key legend using the suggested colors or, if they are feeling creative, they can change the color key to suit their own preferences.
On the 25th, kids will enjoy cutting out the 24 colored boxes and figuring out how the pieces go together to create a hand-illustrated depiction of Jesus' birth.
An alternate implementation is to have kids do the activity in one class setting and bring home the finished piece.
My preview shows an image of the finished (uncolored) picture.