A course on design, engineering, and technology based on Bandura's theory of self‐efficacy was taught to nine science education graduate students who were also practicing teachers. The interpretive analysis method was used to code and analyze qualitative data from focus groups, weekly reflections on classes and readings, and pre‐, post‐, and delayed‐post course questions. The improvement in tinkering and technical self‐efficacies for five males was limited because of initially higher self‐efficacies while that for four females was moderate to high, especially when working in same‐sex teams in a non‐competitive environment. All students also increased their understanding of the societal relevance of engineering and their ability to transfer engineering concepts to pre‐college classrooms. Implementing the principles employed in this intervention in pre‐college science and university engineering classrooms could help recruit students into engineering as well as help retain both male and female undergraduate engineering students.