Cardboard boxes are almost everywhere, but their value is often underestimated. Boxes are valuable for demonstrating the engineering process. For a fun assignment, students can be given a small fan, some boxes, and some paper. Students can work together to try building different designs to try to make some paper or other material float stably. For my experiment, I made a fan stand out of two identical boxes. A tall, skinny cardboard shipping box from Amazon was placed over the fan, creating a wind tunnel. After some crumpling, a piece of paper was able to float in the contraption.