A new method for investigating the movement patterns of children has been developed. It uses a computer analysis and display procedure for reducing Cartesian coordinate position data to numerical and graphical statements about movement patterns. A time-lapse photographic system is used to obtain the position data for children during play. This study explored (1) the potentialities and limitations of this new method and (2) the difference in movement patterns of preschool children with succeeding play sessions. Four groups of preschool children were filmed while engaging in a 15-minute play session during nursery school. Each group was filmed for nine sessions. The playroom was arranged the same way for the first six sessions. On the seventh, a novel apparatus was introduced. The data analysis indicated that as a group the children showed less movement over succeeding sessions. The introduction of the novel object was accompanied by a substantial decrease in movement, with play gravitating to that object. Teacher presence was found to influence movement also. The findings of this study, coupled with suggested revisions of the method, indicate that the technique can be used successfully to collect and analyze children's movement patterns in a closed environment. (WD)