This can be used as a reward system to get students to write more stories and different types of stories. Once a student has done the required writing, they earn the appropriate badge. Use these as you feel appropriate for your classroom and for your students.
It is up to you as to how you display these writing badges. They can have a chart on their locker/cubby that holds the badges, or you can clip them on a necklace like brag tags.
Simply print them on cardstock for durability, or print on full-sheet sticker paper before cutting into separate badges.
I also have badges for reading, spelling, homework, and attendance.