One of the most consistent regularities observers would see in schools is the grouping of children by grade. The authors' work with schoolchildren causes them to ask, what is a grade beyond a group of children at a particular age? In this article, the authors share a glimpse of an activity involving inference and logical necessity that they conducted with three groups of schoolchildren in the fifth grade or higher. The activity calls for at least four children to sit in a circle in front of a class. The teacher secretly writes down the name of one of these children. This person is called the Mystery Person. The rules of the game are very simple. The goal is to figure out the identity of the Mystery Person. The authors found out that the behavior of the children was very different although the activities were essentially the same in all three groups. Their approach ranged from the sort of mastery one might see with mature adults (and a willingness to move on to higher challenges) shown by Group 1, to the atomistic approach employed by Group 2, to the almost complete noncomprehension of Group 3. Some questions and speculations in light of the findings are presented. (Contains 4 endnotes.)