This article explores and compares cross-gender interactions of first and third graders in one child care center. Three prevalent forms of interaction are discussed: teasing, disputing, and playing. The author argues that these three forms of interaction are related to the use of space: Teasing often occurs when space is constricted, disputing is often the result of invaded space, and playing requires shared space and varying levels of cooperation. By focusing on the relationship between space and interaction, important power asymmetries (...) appear. Since boys are more likely to initiate invasions and more likely to determine the rules and terms of the play, they maintain a greater amount of power and control. (shrink)