Informal science learning is valuable in the development of students' cognitive and affective skills which also influences the development of an interest in science. Successful utilisation of informal learning settings into teaching and learning requires highly qualified teachers. This study explored how engagement in a semester-long course influenced preservice science teachers' (PSTs) views and professional development on the use of natural history museums in science education. In this study, researchers collaborated with a natural history museum to design a 14-week-long undergraduate course. Findings revealed that intense immersion to the natural history museum as a part of the undergraduate course helped PSTs to develop a solid understanding of the value of informal settings. At the end of the course, PSTs were able to identify museums as valuable informal learning environments rather than supplemental to classroom learning. In addition, they became more supportive in addressing students' different learning preferences. Accordingly, PSTs defined their teacher role as participants of the student learning process rather than being responsible for organising the visit and managing student behaviour. Most importantly at the end of the course, they were able to make the connection between science curricula and the museum.