Abstract
This study investigated the relationship between the duration of indoor free play periods and the social and cognitive levels of preschoolers' play. The play of thirty-four 4- and 5-year-old children in two preschool class-rooms was observed during 15 and 30 minute play periods over an 8-week period using Rubin's social-cognitive scale. It was hypothesized that the children would exhibit a higher percentage of mature play categories relative to other forms of play during the longer play periods than during the shorter ones. Wilcoxon signed ranks tests confirmed this hypothesis, with subjects being found to engage in significantly higher percentages of group play, constructive play and group-dramatic play in the long periods.