Contribution: This paper demonstrates positive outcomes from reflection-on-action by engineering students, including meaningful insights on their performance, professional and academic practices, and design knowledge as well as promising preliminary exam results. Background: Literature from the engineering education community underlines the benefits of reflection-based upon theories, such as Experiential Learning Theory, and calls for additional use of reflection in engineering education and associated scholarly work. Intended Outcomes: The authors intended for students to obtain meaningful academic and professional insights with implications for their future performance and to perform better on subsequent related exams via reflection. Application Design: Post-quiz and post-design reflective exercises were implemented in two electrical and computer engineering courses, Microelectronic Circuits and Advanced Digital Design, to drive student analysis of differences between their designs or calculations and the "standard solution" using simulation software and question prompts. Reflection-on-action was chosen to enhance students' post-activity understanding and insight, as ultimate learning requires reflection whereby students identify errors and strategies for improvement. Findings: Results demonstrated the value of reflection-on-action using post-activity comparisons and simulation. The students' reflective content and interviews demonstrated substantial professional and academic insights from and appreciation for reflection. On the Microelectronics final exam, a medium effect was associated with the reflection, and for the Digital Design exam, the effect was small to medium. Differences in depth levels of the students' reflections associated with the two types of problems (quiz questions versus design) were evident, suggesting problem type may impact depth.