The purpose of this quantitative study was to determine if there were significant differences in student success in terms of face-to-face and online biology courses as categorized by gender, major, and age; and as measured by lecture grades, lab grades, and final course grades. The data used for analyses included data from 170 face-to-face sections and 127 online sections from a biology course during the fall and spring semesters beginning fall 2008 through spring 2011. Researchers have reported mixed findings in previous studies juxtaposing online and face-to-face course delivery formats, from no significant differences to differences in grades, learning styles, and satisfaction levels. Four research questions guided this study with data analysis involving t-tests for independent groups and chi-square tests. The results of this study enabled this researcher to note significant differences between grades, success rates by gender, success rates by health and non-health majors, non-traditional age (at least 25 years of age) success rate, and attrition rate for students in the face-to-face course compared to the online students. There was no significant difference found in the success rate for traditional age (less than 25 years of age) students in the face-to-face sections compared to those in the online sections.