Studio physics, or SCALE-UP, has been found to improve outcomes such as conceptual understanding, problem-solving skills, and student attitudes when compared to traditional instruction. Such an active-learning environment relies heavily on group work. However, little is known about how best to structure groups and train students to work together effectively. In order to understand the factors that affect group productivity, we must first determine a measure for group effectiveness. We conducted a pilot study on group dynamics in the introductory calculus-based physics sequence at Texas A&M University-Commerce. Videos analyzed were of students working tutorials. Two coding schemes were piloted: behavioral clusters indicating students' epistemological framing and student engagement. Roles assumed by students were also noted. While coding for behavioral clusters and student engagement represented some aspects of group work well, these schemes did not provide sufficient detail to determine group effectiveness.