This research presents an idea to focus on diversity of behaviors of children in after school childcare to evaluate present space composition of facilities and to develop planning policy.<br> Diversity of behaviors means not only individual patterns of variety of acts but relationships with others.<br> Survey was conducted in a after school childcare facility with one room converted from an elementary school classroom, which is surrounded by a school yard available for playing outside. The room is zoned with low furniture into a main zone and smaller corners. Observation research was held in Nov. and Dec. 2011. Acts of children inside in 95 scenes were recorded distinguishing individuals with intervals of 10 minutes.<br> Difference of tendency of acts for areas in a room was found by analysis of kinds, locations and groups of children's acts. Main central zone is mainly for group behaviors and necessary behaviors. Surrounding small corners are mainly for spontaneous behaviors. Acts in groups are mainly done in main central zone and solitary acts or acts with small groups are mainly done in corners. Tendency of acts varies by corners. One corner is used often for active play and the other for group talk.<br> Three characteristic patterns of behaviors were found through individuals' activity analysis. Pattern A is a group of children who tend to act sitting by oneself, pattern B: tend to act sitting in a group and pattern C: tend to act moving.<br> Solo acts of pattern A were found in various location pattern such as one who acts solely beside groups of children, ones who locate in an area next to main area used by groups and one who find small corner to spend time alone. Diversity of sense of personal distance making could be found.<br> Group acts of pattern B were mainly done in main area with low tables. One corner is also used for plays in groups.<br> Moving acts of pattern C include active moving indoor plays and moving acts to find something for next acts. This pattern is considered to appear by relatively faster changes of acts. Locations of acts are dispersed in all the areas including gaps between areas.<br> Children other than these three patterns are understood to be acting with patterns of combination with these patterns.<br> "Idle appearing acts" consists about 10% of all acts, in which the observer could not easily understand their intention and purpose of the acts. "Absent stay", "absently staring" and "roaming" were observed. They are considered to mean resting or adjustment acts to find next acts or next company. They are also a part of diversity of behaviors.<br> Ways to grasp the diversity of behavior of children in after school childcare could be shown through a case study. Relationship between diversity of behavior and space composition in a particular facility was found. Evaluation theory of diversity and planning principle will be developed through continuing comparative study in facilities in various situations.