Although there has been some success with programmes that aim to increase STEM involvement by women and underserved minorities, science educators continue to seek ways to promote students' interest in STEM. This study builds on social cognitive career theory (SCCT) and the theory of enclothed cognition to assess the impact of wearing lab coats on 5th-grade students. Students were assigned to a treatment group (that wore lab coats, n = 106) or a control group (that did not wear lab coats, n = 110) for 10 science classes taught by their classroom science teacher. Students were assessed pre and post to the intervention with a survey designed to measure science interest, recognition from others as a science person, science self-efficacy, and STEM career goals. Results showed students' interest in science was not significantly changed due to wearing the lab coat, but the lab coats did have significant effects on students' perceived recognition by others as being a science learner. Furthermore, those treatment students with low self-efficacy (compared to those with high self-efficacy) and those with who did not report having access to a parent with a STEM career had significant increases in perceptions of self-efficacy in science.