Mission Impastable: Using spaghetti bridges to introduce pre-college students to engineering

Engineering is often a competition between multidisciplinary teams who use interdisciplinary engineering analysis, simulation, and hands-on construction to address a problem that has multiple valid solutions. It can be a struggle to emulate this environment in the classroom, especially when students have only rudimentary knowledge of engineering subjects. One potential vehicle to introduce students to realistic engineering challenges is a survey course for pre-college or first-year students. In this paper we discuss a pre-college engineering survey course with particular emphasis on its spaghetti bridge competition, a project that introduces students to materials science, statics, error analysis, simulation, engineering design, and gives them experience working on a team. Every year hundreds of students devote 20 days of their summer break to learn more about engineering. They complete lab activities in civil, chemical, electrical, mechanical, and materials engineering. They also prepare a presentation in response to a request for proposal, learn about engineering finance, debate engineering ethics, take weekly quizzes, and complete a comprehensive final exam. They participate in a course that has served 4,651 students since its inception in 2006 and 1,073 students in the last two years alone. The core project they complete is a competition to build a bridge that can support the largest mid-span load after accounting for weight and size penalties. The bridge must span 50 centimeters, weigh less than 250 grams, and have a height less than 25 centimeters. The strongest bridges often hold more than 40 kilograms, but teams receive full credit for bridges that hold 3 kg. To accomplish this feat, students experimentally determine material properties of spaghetti, use a virtual lab to design a truss, and prototype and build their bridges to test on the final day of the course. This paper discusses the implementation and outcomes of the spaghetti bridge competition and its role within the pre-college survey course. Based on survey results from an external evaluator, the course significantly increases students' understanding of the variety of work that engineers perform. Students also report increased confidence in their ability to evaluate problems they have never seen before and design and build a structure without a detailed plan. Importantly, they also report that they are more confident about being in a diverse, multicultural group of people. Overall, the project serves its purpose of introducing students to interdisciplinary engineering concepts.