Globally, young people are asking questions about social responsibility. California addresses this in the second draft of its updated mathematics framework, still unreleased as this article goes to press. It defines these questions as authentic, suggesting that classrooms "include, at times . . . contexts students can engage with as a way to understand mathematics as an important tool for participating meaningfully in their community." Teachers can answer this appeal directly through coursework, equipping students to address social and global issues while they learn content standards. Some fear that this social justice spin on mathematics education distracts from the actual mathematics, however this article demonstrates the reverse--how it can make mathematics learning more meaningful and efficient. It introduces an environmental sustainability-centered seventh-grade lesson series that simultaneously marries mathematics with the engineering cycle, answering a concurrent call to promote engineering mindsets.