This chapter presents an innovative approach to equipping generalist primary pre-service teachers with essential competencies and enthusiasm for effective STEM education. It explores the transformative experiences of a postgraduate-level cohort of pre-service teachers who participated in an immersive STEM course as part of their initial teacher education program. What distinguishes this study is the diverse backgrounds of the pre-service teachers, many of whom are ‘career changers’ bringing rich experiences from various fields. The primary focus of this research is to examine how the immersive STEM course influenced the learning and teaching perspectives of these pre-service teachers, as well as the educator who designed and facilitated the course. Practice architectures provided the framework for analysing the data by offering insights into how the course design and interactions within the learning environment influenced participant outcomes. To gather these insights, a combination of research methods was employed, including surveys and focus group interviews. Surveys captured information on pre-service teachers' confidence and experience from the STEM course, while focus group interviews explored their reflections, and the challenges encountered during the course. Findings are presented through narrative vignettes that feature the voices of the pre-service teachers and the educator involved in course design and facilitation.