The purpose of this teacher research study is to ascertain students' interest in STEM and beliefs about STEM before and after STEM specific instruction, explore possible differences in STEM self-efficacy by gender, and explore differences in STEM self-efficacy by group role. Our primary data sources include a modified attitudinal survey and modified perceptions of collaboration survey. We found differences in gender and students' group roles to be related to self-efficacy, intentions to persist in STEM, perceptions of STEM and interests in STEM. Research on students' self-efficacy and perceptions of group work has the potential to restructure how teachers design activities and teach students about collaboration.