Inquiry-based learning is a well-known strategy in STEM education. It aims to enhance conceptual learning, acquisition of scientific practices, and reflecting on the Nature of Science. However, evidence indicates that in practice, inquiry is often taught in a narrow, mainly experimental approach. This interpretive study analyzes teachers explicit and implicit views regarding implementing inquiry-based learning. The participants enrolled in three professional development programs. They were engaged in multiple genres of inquiry and were encouraged to design an inquiry activity. Data sources included observations, interviews, questionnaires, assignments, and reflections. Findings indicate that with regard to inquiry implementation, teachers were highly concerned about their students’ competency and their own’s working context. Teachers who discussed mostly challenges often designed a narrow-controlled inquiry, while teachers who reflected, negotiated, and challenged their initial views addressed more epistemic aspects of inquiry. Implications for supporting teachers’ development of a broader approach to inquiry learning are discussed.