Holiday Fun at Bertha Bartlett Public Library. The First Annual Gingerbread House Challenge for Tweens and Teens took place at the library on December 11. In teams of two to three, the youth built holiday houses using graham crackers, royal icing and a selection of candies and baking supplies. All of the houses that survived the challenge are on display in the library. It was a chaotic and fun afternoon of creativity and laughter.