A common issue in student design projects is the size, storage, and transport of projects faced by teachers after a project is complete. We aimed to find a low-cost way to contain a project and manage the footprint of the overall designed paper mechatronics product. Because cardboard file boxes are readily available at office supply stores and easy to stack and move, we created a design project for high school teen interns called the Mechanical Cardboard Theaters. The theaters were made from file boxes, and prototyped and tested with visitors at the science center. Teens had 5 hours of studio time to create a design in a team of 2-3 students. A door to the theater would open and shut (driven by a set of linkages, servo motor, and Arduino UNO or Hummingbird board) after a motion sensor was triggered. After teens received feedback, then tweaked their code and mechanisms. While teens could choose what their theaters could display, teens were told that their designs would be shared publically with families in the museum and at Maker Faire Bay Area 2015.