We describe an interactive table designed for supporting face-to-face collaborative learning. The table, Reflect, addresses the issue of unbalanced participation during group discussions. By displaying on its surface a shared visualization of member participation, Reflect is meant to encourage participants to avoid the extremes of over- and under-participation. We report on a user study that validates some of our hypotheses on the effect the table would have on its users. Namely we show that Reflect leads to more balanced collaboration, but only under certain conditions. We also show different effects the table has on over- and under-participators.