Following the growth of online, higher-education courses, academic institutions are now offering fully online degree programs. Yet it is not clear how students who enroll in fully online degree programs are similar to those students who enroll in in-person ("traditional") degree programs. Because previous work has shown students' attitudes toward science can affect their performance in a course, it is valuable to ask how attitudes toward science differ between these two populations. We studied students who completed a fully online astrobiology course. In an analysis of 451 student responses to the Classroom Undergraduate Research Experience survey, we found online program students began the course with a higher scientific sophistication and a higher sense of personal value of science than those in traditional programs. Precourse attitudes also showed some predictive power of course grades among online students, but not for traditional students. Given established relationships between feelings of personal value, intrinsic motivation, and, in turn, traits such as persistence, our results suggest that open-ended or exploration-based learning may be more engaging to online program students due to their pre-existing attitudes. The converse may also be true, that certain pre-existing attitudes among online program students are more detrimental than they are for traditional program students.