Rapid advances in science and engineering, and pervasive adoption of resulting technological products, are influencing every aspect of human living and fueling a growing demand for a workforce that is adequately prepared for the emerging occupations in STEM fields. Educating students for success in the modern technology-rich workplace requires teachers who have the knowledge, comfort, capability, and training to adopt and integrate new technologies for classroom teaching and learning. Thus, to prepare high school teachers for incorporating robotics in their students' education and promoting their understanding of engineering concepts and technology applications, a four-week long robotics workshop was designed and conducted annually for three summers. Examination of changes in the workshop participants' levels of robotics self-efficacy, familiarity, and content knowledge, as well as analysis of outcomes of robotics capstone projects and end-of-year contests, is suggestive of study findings being promising for education researchers and professional development providers interested in leveraging the potential of robotics in STEM education.