This article reports on the results of the authors' research and development work that was designed to study the impact of internships in scientific laboratories on high school students. The authors sketch how the internships affected cognitive outcomes, experiences and attitudes, and the career aspirations of the high school students. The internship experiences were highly successful in that the high school students came to learn scientific knowledge and skills they did not know before. They also developed understandings of what science generally and environmental science more particularly is about. However, the internship did not make a difference in terms of making this science an attractive career for 10 out of 11 students involved. One explanation may be the fact that students already found themselves in advanced high school science courses and already had well-established ideas about what they wanted to do. The experience with the students also shows that internships, to be effective recruiting mechanisms, should permit students to become involved actively in the research rather than being mere onlookers. Consequently, science should welcome the participation of people with different ways of knowing and worldviews; scientific biology needs to adapt and adjust itself as such to be more inclusive and to recruit a more diverse mixed population of students. (Contains 1 figure.)