Introductory biology courses at two-year, open enrollment colleges in America are presented in a variety of different course delivery formats. Traditionally, most students have enrolled in seated or face-to-face (F2F) lectures and laboratories. There is increased demand for courses presented online or in a hybrid format, although some studies report higher attrition rates, and lower grades for these course delivery formats. The purpose of this study was to examine if there were academic differences among F2F, hybrid, or online introductory biology courses by analyzing precourse and postcourse assessment scores, final grades, attrition rates, and students' perceptions of course satisfaction. This study was grounded in the social constructivist conceptual framework and followed a mixed method design. Four research questions guided the study which involved the collection of both quantitative and qualitative data. The study involved 354 adult students enrolled in three, open enrollment, two-year institutions in Southern Missouri. Statistical analysis indicated significantly higher mean gain scores on postcourse than precourse assessments, regardless of location or course format. There was a significant difference in final course grades for students enrolled in online courses compared to those in F2F or hybrid sections; students enrolled in online sections also had a significantly higher attrition rate. Seven focus groups were conducted, and students completed online surveys indicating their satisfaction level. This study had direct application to the design, implementation, and assessment of introductory biology courses and provided insight into students' academic success and perceptions of course satisfaction with introductory biology classes. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]