Background: The linkage between group members' characteristics, group cohesiveness, knowledge application, and competitive performance has rarely been studied. Purpose: This study aimed to explore the correlations among individual characteristics (i.e. prosociality), collective mind (i.e. collective efficacy and cohesiveness), and how these variables affect scientific knowledge application. Sample: This study examined a STEAM (science, technology, engineering, arts, and mathematics) competition, called the GreenMech contest, which required four members in a group to assemble all parts into many configurations for a ball to run and trigger the next junctures. Design and methods: The competition groups assembled their configurations in the morning, with judges assessing their efforts in the afternoon. The bulk of the scoring index in the assessment focused on groups' scientific knowledge application in the overall design. In addition to this assessment, this study additionally used questionnaire surveys for participants to self-rate their perceptions of those individual traits and collective states. Results: Prosociality is positively related to collective efficacy and cohesiveness, while collective efficacy is positively related to cohesiveness. Moreover, these two types of collective mind were both positively related to the application of scientific knowledge. Conclusion: The findings suggest that team members with a higher level of prosociality may provide collective efficacy and cohesiveness, which in turn can facilitate their achievement of competition goals by increasing their application of scientific knowledge in a STEAM contest.