Teaching digital circuit design to middle-school students

During the summer of 2012, the Electrical Engineering department at the University of Minnesota Duluth offered a summer camp for seventh-grade students to attempt to interest them in engineering. Among the topics included in this one-week summer camp was a one-day exposure to digital circuit design. How does one teach digital circuit design in one day to students who are in the midst of summer vacation and who have no technical background? What are the vital basics? What is unnecessary confusion? How can seventh-graders be entertained while still inspiring them to consider engineering concepts? These questions were among those faced by the Electrical Engineering faculty. This paper exposes some of the techniques used to intrigue students and to capture their interest in digital circuit design. Attracting middle-school students to the field of engineering is a challenge. Students' interest must be captured before societal pressures deflect career choices into other directions. Students, must be encouraged to consider engineering as an interesting field before it is "too late" to enter the necessary math and science tracks in high school. Consequently, students must be exposed to the excitement and potential of engineering during their middle-school education to motivate them successfully to consider engineering careers. The goal of the summer camp was to dazzle students with fun applications that engineering makes possible, without intimidating them with undue complexity or technical details. Topics presented to these seventh-graders during their one-day exposure to digital circuit design included both combinational and sequential circuits, although only in very restricted arenas. Only two different types of digital components were described, NAND gates and D-flip-flops. A seven-segment LED display digit was used to show the output produced by student circuits because these students were familiar with such displays from their everyday life. Students performed a variety of experiments from simply making a light flash to creating custom patterns on the seven-segment display, with a wide range of success. Overall, students seemed to enjoy the experience. This paper describes the topics presented to these middle-school students in digital circuit design, and details some "lab experiments" performed to provide hands-on experience. Also included are lessons learned by the Electrical Engineering faculty to improve future camp offerings.