There are strong classroom ties between mathematics and the sciences of physics and chemistry, but those ties seem weaker between mathematics and biology. Practicing biologists realize both that there are interesting mathematics problems in biology, and that viewing classroom biology in the context of another discipline could support students' development of biology understanding (as mathematics does for physics and chemistry). The Biology Levers Out Of Mathematics study, implemented in public and private schools throughout a metropolitan area in the northeastern United States, tackles this challenge by introducing engineering as a bridge connecting the heretofore isolated silos of classroom mathematics and biology. This study presents engineering design methods for students to use in the posing of biology problems that mathematics then makes possible to resolve. Interviews with teachers and observations of students suggest that this approach makes the understanding of inheritance processes accessible to a wide range of the study's participants.