Digital tabletop surfaces afford multiple user interaction and collaboration. Hybrid tabletops that include both tangible and multi-touch elements are increasingly being deployed in public settings (e.g. Microsoft Surface, reacTable). Designers need to understand how the different characteristics of tangible and multi-touch interface elements affect collaborative activity on tabletops. In this paper, we report on a mixed methods exploratory study of a collaborative tabletop game about sustainable development. We explore the effects of tangible and multi-touch tools on collaborative activity. Forty-five participants, in trios, played the game using both versions of the tools. Our analysis includes quantitative performance measures, qualitative themes and behavioral measures. Findings suggest that both tangible and multi-touch tools enabled effective tool use and that collaborative activity was more influenced by group dynamics than tool modality. However, we observed that the physicality of the tangible tools facilitated individual ownership and announcement of tool use, which in turn supported group and tool awareness.