This study analyzes educators' conceptions of STEM education at the beginning of an online graduate course for in-service teachers. It offers a qualitative thematic analysis of educators' initial conception of STEM education and their roles as STEM educators through the use of concept maps and reflection statements. Conceptions of STEM varied greatly across the sample and fell into seven categories: (a) utilitarian, (b) acquisition of disciplinary knowledge, (c) activities and resources, (d) meaningful problem-solving experiences, (e) advocacy for systemic change, (f) buzzwords, and (g) educator's role in STEM teaching and learning. This study reveals the complexity of educators' ideas of STEM and educator roles within STEM education. Using concept maps as formative assessments can better position teacher educators to provide structured reflection space for educators while aligning coursework and resources to better meet educators' varied needs.