The purpose of this research assignment is to reflect and discuss the authors' personal experiences with human behavior and connect them to theory and research. Examine and inform changing experiences as a member of a small experimental group in the classroom; Apply various topics taught in Behavior In Groups (Psyc 3430) and investigate various experiential learning opportunities about group behavior in the classroom. The author had experiences with two groups in class: Group 4, "Jordan's get it done" and Group 20 "Indugio". The demographics of both groups were quite similar as the members were all students at the University of York. Group 4 consisted of members A, B, and C (males aged 21–26 years) and member D (female aged 36 years). Group 20 consisted of members A, E, and F (males aged 23 to 27 years) and members G and H (females aged 22 to 25 years).I. Group Formation and StructureGroup DevelopmentWhen new members joined Group 4, the author observed various effects on group development. Adding members to the group "resets" the group and/or creates a new group that is completely separate and unique from the original. As new members joined, the old relationship between members deteriorated and new ones emerged. These effects were found in Group 4 with the addition of new members: in class no. 2 member C joined and in class no. 3 member D joined. Changes in group composition created tension towards older group members, decreased self-confidence and stressed performance, as the author observed from patterns and behaviors member communication. New members joining the group significantly interfered with the completion of classwork as meeting new members and presentations on group norms and roles took some time to rearrange... half of the paper. .. expert power of member A was positively correlated with compliance and competence. Conclusion With reference to the various studies and experiments, the authors' experience on classroom groups was elaborated. By connecting theory, research, and reading journals on group development, conflict, and leadership, the author has gained an enriched perspective and understanding of his experiences. Taking what was taught in class and at home, the author experienced "real-time" experiential learning about the behavior of class groups. The limitation of the authors' classroom experiences concerns the short duration of experiential learning opportunities. For a duration of about just three months, members met in class only once a week and occasionally communicated outside of class via email. A longer duration is preferable to obtain more precise and astute observations.