Objectives: Exposure to radiology in undergraduate medical education is often restricted by other curriculum demands. Designing an effective radiology elective for medical students who choose to supplement their education can be challenging as it is often a passive observership-style elective. In this study, we examined the impact of incorporating an online learning platform and electronic book into radiology electives to stimulate active learning. Materials and Methods: We enrolled 23 students who pursued a 2-week diagnostic radiology elective at our institution. Their radiology knowledge prior to the elective was assessed using 2 pretests. Students had opportunities to work with radiologists to review clinical imaging, attend academic rounds, and learn from the online learning resources. Their knowledge after the elective was assessed by readministering the 2 tests as “posttests.” Students also ranked their perception of the elective experience and educational resources on a Likert scale from 1 to 5. Results: There were statistically significant increases of 13.4% ( P < .0001) in mean test 1 scores and 6.8% in mean test 2 scores ( P = .001). Students also had favorable perceptions of the radiology elective experience and rated the electronic book (median score: 5 of 5) and online learning platform (4.5 of 5) as valuable educational resources. Conclusion: The implementation of an electronic book and online learning platform improved knowledge in radiology and resulted in positive student perceptions of the elective experience. This supports the use of online resources to facilitate independent self-learning for future radiology electives.