A physics student's identity is predicated on a multitude of factors, such as research, classes, and activities outside the classroom. Many students choose to participate in informal physics teaching programs during college; however, these programs are an understudied portion of a physics student's experience. We hypothesize that university students' science identity is reshaped by interactions and experiences they have in these programs. We focus on a student group that does demonstrations at local K-12 schools and organizations. Pre- and post- interviews were collected with undergraduate participants in this group who went on an intensive week-long trip to rural areas in the state. Here, we extend our previous work using a Communities of Practice framework to analyze these interviews. We operationalize students' movement toward or away from central membership as well as look at the intersection of other physics, academic, and personal communities with the informal physics program community.