Natural history museums (NHMs) are important out-of-school learning settings for teaching science; therefore, familiarisation with NHMs is crucial for future teachers. This article presents a student teacher training program in the form of an optional module for Master of Education Biology students at a major German university that focuses on NHMs as out-of-school learning settings and important places of research. The course first imparted content as well as background knowledge about NHMs and their tasks and then provided the possibility to test a teaching unit that was designed by the student teachers with school students in a museum. In all, 27 student teachers participated in this study, which combined qualitative and quantitative data to evaluate the effects of the course. Data were supplied from 3 different sources: (a) a questionnaire in a pre-/posttest design, (b) reflective writings of the participants concerning the course, and (c) protocols of group discussions that were conducted before and after the course. This study shows that the course imparted background knowledge and raised awareness of the value of NHMs for research and as out-of-school learning sites. The gain in content knowledge concerning museums not only could be measured in the pre-/posttest design but also was perceived by the students themselves. The students experienced the inclusion of practical work with school students in an out-of-school learning setting, a look behind the scenes, and the involvement of museum professionals and scientists as extremely valuable elements of the teacher education program.