%AGunning, A.%D2021%I %K %MOSTI ID: 10330650 %PMedium: X %TStudying In-service Teacher Professional Development on Purposeful Integration of Engineering into K-12 STEM Teaching (Research to Practice) %XIntegrated STEM approaches in K-12 science and math instruction can be more engaging and meaningful for students and often meet the curriculum content and practice goals better than single-subject lessons. Engineering, as a key component of STEM education, offers hands-on, designed-based, problem solving activities to drive student interest and confidence in STEM overall. However, K-12 STEM teachers may not feel equipped to implement engineering practices and may even experience anxiety about trying them out in their classrooms without the added support of professional development and professional learning communities. To address these concerns and support engineering integration, this research study examined the experiences of 18 teachers in one professional development program dedicated to STEM integration and engineering pedagogy for K-12 classrooms. This professional development program positioned the importance of the inclusion of engineering content and encouraged teachers to explore community-based, collaborative activities that identified and spoke to societal needs and social impacts through engineering integration. Data collected from two of the courses in this project, Enhancing Mathematics with STEM and Engineering in the K-12 Classroom, included participant reflections, focus groups, microteaching lesson plans, and field notes. Through a case study approach and grounded theory analysis, themes of self-efficacy, active learning supports, and social justice teaching emerged. The following discussion on teachers’ engineering and STEM self-efficacy, teachers’ integration of engineering to address societal needs and social impacts, and teachers’ development in engineering education through hands-on activities, provides better understanding of engineering education professional development for K-12 STEM teachers. Country unknown/Code not availableOSTI-MSA