In the United States, the Next Generation Science Standards (NGSS) bring both commitment and challenges to science education in K-12 schools. New focus areas within the NGSS are engineering education and the integration of multiple disciplines as seen in science, technology, engineering and mathematics (STEM). Providing professional development (PD) is necessary in order to assist K-12 teachers with the implementation of the NGSS in their classrooms (NGSS Lead States, 2013). This case study shares the results of a unique style of PD workshops provided for K-12 teachers on the NGSS and engineering design where participants were immersed in inquiry-based STEM activities with an earth and space science theme. Twenty-six teachers agreed to participate in the study. This qualitative research focused on self-reported data through surveys, interviews, focus groups, and observation of participants during the workshops. Findings from this case study revealed self-reported increases in teachers’ dispositions and self-efficacy regarding their implementation of the NGSS in an integrated STEM teaching context.