We report the results of field study that qualitatively reveal the usefulness of collaborative researcher-robot presentations in a science museum from the viewpoints of (1) understanding the general public's thoughts on robots for children, (2) conveying information on robotic literacy to the general public, and (3) creating researcher-people interaction while walking together with a robot after a presentation. In robotics research for children, researchers need to deepen their understanding of the general public's expectations and concerns about robots, and the general public needs to deepen their understanding of the capabilities and limitations of robots. We believe that a collaborative researcher-robot presentation in a science museum allows for these, and also has the potential to generate discussions between a researcher and the general public in other scenes than presentations, through walking together with a robot. In this study, the first author and a robot conducted 16 series of science communication activities on robotics research in a science museum, in which more than 433 people participated in total. We evaluated these practices based on the first author's participant observation. We confirmed the usefulness of collaborative researcher-robot presentations in a science museum from the three perspectives, and also obtained unexpected findings that may have been obtained thanks to the first author's participant observation in the field. Our findings should be useful in conducting discussion activities with the general public regarding the research and development of robots that interact with children, and in considering how to show mobile robots in public spaces in a friendly manner.