Genetic engineering is taught in biology--but as a scientific tool and not as a means to explore engineering design. Yet, given the clever behaviors and patterns that can be found when examining living systems, biology classes seem well positioned to teach foundational engineering design principles (Kuldell 2007). This article examines a new, open-access curriculum designed to do just that: BioBuilder is the product of collaboration between the Massachusetts Institute of Technology's (MIT) Department of Biological Engineering and local high school teachers. It draws from the relatively new field of synthetic biology, an engineering approach to the design of novel living systems or the redesign of existing ones. Just as physics teachers have students create functioning electrical circuits or robotic systems, biology teachers can have students safely design, construct, and analyze engineered biological systems. (Contains 4 figures and 5 online resources.)