This paper reports on the use of a new survey instrument, the S-STEM survey, as a model for data-driven decision making both formal and informal K-12 STEM education initiatives. Current national policy and research findings regarding K-12 STEM pipeline initiatives note the importance of enhancing both cognitive (i.e., content) and affective outcomes of students with regards to STEM subject areas, and that both formal and informal education strategies are likely to be needed to address the larger goals. The Friday Institute for Educational Innovation’s Evaluation Group and the MISO project at North Carolina State University jointly undertook the development of a set of common instruments that could be used to assess the affective impact of K-12 STEM educational innovations in both formal and informal settings. Over 10,000 4-12th grade students from across North Carolina that were in special STEM initiative schools were surveyed, providing baseline data on STEM attitudes towards STEM subjects and career trajectories. These results were discussed in terms of how they can be used by K-12 STEM outreach programs that have partnered with the MISO project to help guide the formative assessment of the efficacy of their programs and guide future strategies.