The most important part of an advent calendar is the count down. Print some numbers off yourself using this template from Simple as That. You can do it on brown paper or white and attached it to anything you want to use.
DIY Advent Calendar - Add Photos, Poems, Recipes, Artwork, and Momentos. Great to give as a gift already customized to the recipient, or give early so the family can make its own! Can be updated every year, or kept the same to become a family heirloom.
árbol de navidad y calendario de adviento
24 Creative Homemade Advent Calendars! - Things to Make and Do, Crafts and Activities for Kids - The Crafty Crow
Pop-Up Advent Calendar - Nativity Tree
I think this would be cool for something else. Not sure what yet.
Peppermint Bark Cheesecake - It has three delicious layer-Oreo crust, creamy cheesecake filling loaded with peppermint bark pieces and white chocolate ganache on top garnished with crushed candy canes, whipped cream and chocolate.