Graduate College. iv DEDICATION I dedicate this to my family for supporting and encouraging me along the way. To my husband Brian, daughter Hadley, son Owen, and little dog Smokey.v ACKNOWLEDGEMENTS This has been an incredible journey and I have so many people who have guided and supported me along the way. First and foremost, I would like to thank my committee members. To my advisor, Sara Hagenah, a wonderful mentor who met with me frequently over the past two years and always offered guidance, support, and words of encouragement through the most challenging parts of this process. To Julianne Wenner, who got me started on this topic by assigning her students to write a dissertation proposal in class and helped me develop a clearer focus for my research. To Kara Brascia, for her dedication to service-learning and for her thoughtful feedback. To Keith Thiede, for joining the committee at the last minute and spending so much time helping me with the quantitative analyses that were so challenging. I would also like to thank Beau Hansen for his earlier contributions to this committee. Finally, I would like to thank my family and friends for their support. To my husband Brian for encouraging me all the way through even when it was stressful, to my daughter Hadley for being so helpful and kind, to my son Owen for making me laugh, and to my dog Smokey for making me take frequent breaks in the foothills. Thank you also to my parents, Robert and Gwenda, and to parents in-law, Linda, Dennis, Mike and Marcia, for their words of encouragement and support as I achieved this major life accomplishment.vi ABSTRACT Service-learning (SL) is a high-impact pedagogical strategy that has been shown to have both cognitive and affective benefits for students and has the potential to engage and involve a more demographically diverse spectrum of students into the field of STEM.However, research on the impacts of SL in STEM courses is limited, and therefore there is a great need to identify the specific outcomes linked to participation. In addition, faculty from STEM fields have been hesitant to incorporate SL into their curriculum due to perceptions that it lacks academic rigor. This purpose of this mixed-methods case study was to examine how participation in SL in an introductory environmental science course specifically impacted students' knowledge of course content and development of agency, both at the projects and beyond. Students in the study participated in a range of different SL projects through the course. SL outcomes were compared across different types of SL projects to determine the overall impact of SL on course content and agency growth, as well as to more effectively assess the general characteristics of projects that fostered growth in these areas. The findings from this study showed that SL participation led to increases in both course content knowledge and agency. Students with high course content knowledge growth also had exhibited high agency in the projects. The findings did not, however, show any significant differe...