Today's elementary teachers are expected to teach the engineering practices included in the National Research Council's Framework for K-12 Science Education and the Next Generation Science Standards. Recent studies have indicated that teachers are less self-efficacious in teaching engineering than in other subject areas. Project Lead the Way (PLTW) is a nonprofit organization that offers pre-K-12th grade curricula and teacher training focused on three pathways: engineering, computer science, and biomedical science. Due to the COVID-19 pandemic, PLTW transitioned its teacher trainings to a virtual modality. At the time of this study, most of PLTW's teacher training remained virtual or hybrid. The purpose of this study was to examine the extent to which elementary teachers' teaching engineering self-efficacy, engineering design process self-efficacy, and mindset changed over the course of participation in PLTW Launch professional development during the summer of 2023. This study utilized a quantitative pre/post-test survey design. Pre- and post-training surveys comprised demographic questions, the Teaching Engineering Self-Efficacy scale (TESS), the engineering design self-efficacy subscale of the Engineering Design Self-Efficacy Instrument (EDSI), and the Growth Mindset Scale. Twenty participants from South Dakota, North Dakota, Louisiana, and Nevada completed the pre- and post-training survey. Descriptive statistics, change scores, and paired sample t-tests were used to analyze the results of the pre- and post-training surveys. Results suggest that teachers who completed PLTW Launch training experienced statistically significant increases in their teaching engineering self-efficacy and self-efficacy to conduct engineering design. Additionally, statistically significant increases were found for the constructs of engineering pedagogical content knowledge self-efficacy and engineering disciplinary self-efficacy. No statistically significant differences between pre- and post-training surveys were found for the construct of engineering engagement self-efficacy or mindset. Implications of this study suggest that PLTW Launch training is a viable option for improving elementary teachers' confidence to teach engineering in their classrooms. Results of this study add to the limited research on teaching engineering self-efficacy. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]