In July 2008, a new professional development program called Satellites, Weather and Climate (SWAC) began at the University of Vermont. Its goal was to enhance the competency of in-service K-12 science and mathematics Vermont teachers in the atmospheric, climate, and geospatial sciences. The pilot program ran until 2010, during which time 14 teachers representing three cohorts were exposed to the eight training modules developed specifically for the program. The SWAC program is social constructivist in nature and implemented in such a way that participating teachers built upon prior SWAC content knowledge with each passing year in the program. SWAC modules were based on inquiry, problem, and project-based techniques and were presented in lectures, outdoor observation, and remote sensing laboratory settings. Participating teachers typically began the program during a weeklong, intensive summer program that covered the core SWAC concepts and skills. This was followed by two 1-h workshops every month during the academic year in which participants focused on a specific content module, geospatial skill, or technique. These content and skill workshops alternated with lesson planning sessions to allow teachers to develop lessons, units, or projects with SWAC materials. Program effectiveness was quantified by pre- and posttest evaluations of the modules, a SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis in January 2010, and a comprehensive survey of participants' pedagogical changes, as well as the skills and attitudinal changes of the 927 students they taught during the pilot phase. Teachers reported that participation in SWAC transformed their pedagogical approaches and in-class effectiveness while dramatically improving their students' observational abilities, critical thinking skills, and understanding of geospatial technology. An additional outcome of the SWAC program was the Teacher Learning Community that developed, in which participants were able to share activities and challenges across grade levels, school systems, and institutional barriers in a setting not found anywhere else in their professional development environments.