The present study assesses the efficacy of a semester-long undergraduate sustainability curriculum designed from a systems approach. The three-course curriculum, which incorporated environmental science and ethics courses along with an integrative course using a community-based learning pedagogy, was intended to provide students with experience using knowledge and skills from distinct disciplines in a holistic way in order to address the complex problems of the human acceptance of and response to anthropogenic climate change. In the fall of 2013, 23 of the 24 sophomore general education students enrolled in the three courses were surveyed at the beginning and end of the semester; 17 of those same students completed the survey again in the spring of 2016, their senior year. Results, which focus on the 17 students who continued to participate through their senior year, were analyzed with quantitative and qualitative methodologies. The pre/post data from the surveys demonstrated significant improvement in climate literacy, certainty, concern and urgency over the course of the semester; the senior data indicated that those improvements were largely retained. The study also suggests that the nine-credit curriculum improved transferable skills such as interdisciplinary thinking, self-confidence and public speaking. A qualitative analysis of three student cases, informed by a focus group (n = 7) of seniors along with other sources of information, suggested retention of such transferable skills, and, in some cases, deeper involvement in climate and sustainability action.