Self-efficacy is important for success in computing courses, but best practices for how computing instructors can support students’ self-efficacy development are still a matter of ongoing development. CS students’ judgments about their own abilities are often very self-critical and disagree with the ways that experts in CS would measure competency. Self-assessment scaffolding has been observed to improve learning outcomes and self-efficacy in various domains. However, these practices are not well known in CS education research, and there is a lack of empirically-based guidance about how to implement them. This project is devoted to developing a self-assessment scaffolding intervention for CS1 that is effective, efficient to implement, and usable for students. Improving pedagogical practices in introductory courses (CS1) will help improve the outcomes for everyone, but approaches targeting self-efficacy may particularly benefit students from minoritized groups in CS, such as women and students of color.