A course-based undergraduate research experience (CURE) is described, both in its original, field-based and in-person design, as well as its adaptation to online delivery during the COVID-19 pandemic. The CURE experience was centered around the topic of microbes attaching to ocean plastic debris, and included connecting nontraditional undergraduate students attending a primarily teaching institution to personnel of a research-intensive institution. The CURE was implemented in nonmajors and majors’ general biology laboratory courses, as well as in an introductory microbiology lab course for health majors. Student perception of the CURE was assessed quantitatively through self-administered retrospective surveys, and qualitatively using open-ended survey questions and focus group interviews. Survey questions were grouped into four themes: (1) research at the research institution, (2) research at the teaching institution, (3) laboratory skills, and (4) interest in science. To assess impact of the CURE by modality, major and course level, theme scores were analyzed using ANOVAs (α = 0.05). Changes in student perception of learning were measured by comparing the “before” and “after” survey scores in each theme. The main source of variation in the model was time, followed by theme and major, while modality had a negligible effect. Overall, there were increases in student perception of learning across all themes across modality, major, and course level; however, not all were statistically significant. Highest gains were observed among nonmajors, while those of the majors’ upper division courses were the lowest. On the other hand, majors’ overall scores were the highest. Health majors’ survey gains were mostly between those of nonmajors and majors. Qualitative data contextualized the quantitative results. The online adaptation was a valuable alternative, especially for nonmajors, as it expanded the range of students reached, with results similar to the in-person alternative. Preliminary data show a positive effect of the CURE in student success majoring in biology.