In this paper, we present SCAMP -- Social Configuration Affordances for Museum Play -- an analytical framework we develop and use to highlight the relationship between designed affordances at interactive museum exhibits and different social playful behaviors they trigger and support. We do this through a selective case study analysis of Rainbow Agents, an interactive museum exhibit designed to support play across multiple social configurations. This variety of configurations is valuable for museum settings, as it helps museum visitors engage with each other according to their preferences and also enables the emergence of modes of collaboration and competition novel for learners in such contexts. Our SCAMP analysis of Rainbow Agents sheds light on design features which successfully support different forms of productive social play -- including short and long episodes of competitive, collaborative and parallel play, spanning play, teaching, and receiving interpersonal interactions. In particular, we pay attention to behaviors representing a variety of mentoring and learning opportunities -- in line with and extending the vision and goals of educational games' and science museum exhibits' designers and researchers.