There is wide consensus among educators that participation in authentic research is valuable for undergraduate science students, and incorporating research into large-enrollment courses is one way to provide that opportunity to many students. There is substantial variation in the documented impacts, however, particularly between males and females. To begin to address this variation we examined attitudes about science before and after courses that included original research. Students collected novel data documenting local biodiversity and communicated those data to the scientific community through an international database. Results from surveys suggest that these courses had a gender-specific effect--the attitudes of female students changed more than those of male students, and prior research experience affected the change in attitudes of female students but not male students. In focus groups both males and females emphasized that making contributions to science was a critical aspect of this project. Although both genders were equally cognizant of their contributions, previous studies suggest that placing science in context may be more important for female students.