This study examined the effects of an Arduino microrobot activity on college students' interest in robotics through three specific objectives: (1) determining how students' conceptual understanding regarding the basics of microcomputing and computer programming changes after engaging in an engineering robotics learning module, (2) assessing the impact of these changes on students' sense of competence in engineering robotics, and (3) explaining the role of students' perceived knowledge transferability in the relationship between their sense of competence and changes in their interest for pursuing engineering robotics. Participants (n = 58) were recruited from two Engineering Physics courses and surveyed before (Time 1) and after (Time 2) an Arduino microcomputing learning activity. First, significant increases were reported post-activity for interest in robotics, as well as conceptual understanding of microelectronics and computer programming. Second, changes in the understanding of computer programming significantly predicted students' sense of competence at Time 2. Finally, high and low levels of competence and perceived knowledge transferability were related to changes in students' interest in robotics. Moreover, high levels of perceived knowledge transferability alone played an important role in students' interest in robotics. Transferring complex engineering ideas to novel situations was beneficial regarding students' learning gains associated with computer programming and with the Arduino microcontroller platform. An overview of the virtual lab architecture used is provided with suggested novel directions for teaching college-level courses about engineering robotics.