Centennial runs its own postal system. Students serve as post masters and mail carriers. Each classroom and office has its own 'street address' and students and staff write letters to each other. Mail is picked up and delivered in the morning and afternoon before and after school. Third, fourth, and fifth graders participate in our post office by picking mail up, sorting it, and delivering it. Writing letters is obviously a real world skill we want our students to have and this gives them an opportunity to write to other Centennial community members for authentic purposes. We even have our own stamps that must be used (the stamps are provided at no charge).