NASPE recommends preschoolers receive at least 60 minutes of structured physical activity (PA), 60 minutes of unstructured PA, and not be sedentary for more than 60 minutes at a time. Nearly 56% of 2-5 year old children spend all or part of their day at preschool. The preschool environment can have a major influence on daily PA. Few studies have been reported examining methods to increase PA of preschoolers in the preschool setting. The purpose of this study was to compare the PA levels of preschool children while engaged in normal playground breaks and after enhancing the playground with additional portable activity equipment. Participants were 76 preschoolers aged 3-5 years recruited from a Child and Family Development Center, located at a University. PA was quantified using Actigraph GT1M accelerometers. A quasi-experimental design was used to compare PA levels in two play settings. Data collection began with five days of normal playground breaks. The standard outdoor play area was equipped with three multi-purpose play apparatus, a play kitchen, and a basketball hoop. The children then participated in five days of enhanced playground breaks. The enhanced play area was designed into a developmentally appropriate obstacle course in which the children participated in locomotor and nonlocomotor activities. Accelerometer count cut-points specific to 3-5 year old children, using a 15-s sampling interval, were applied to the data to determine the percent of break time spent in sedentary, light, moderate, and vigorous PA. Preliminary analyses revealed no significant main effect for gender. A 2 x 5 x 3 (Intervention x Days x Age) analysis, with two within subjects factors and age as a between subjects factor were tested using SPSS GLM repeated analysis software. Dependent variables were the proportion of time spent in each PA intensity category. The intervention resulted in a significant decrease in sedentary PA and significant increases in light, moderate, and vigorous PA. Age effects were also significant, with significant effects for light, moderate, and vigorous PA intensities. The age effect was modified by a significant age by intervention interaction. The interaction was significant for moderate and marginally significant for vigorous. The interactions show that the youngest children have more moderate PA than the older children while the oldest children have more vigorous PA than the youngest children. In conclusion, a simple playground intervention was effective in reducing sedentary activity, and increasing light, moderate, and vigorous PA in preschool aged children. Keyword(s): early childhood, exercise/fitness/physical activity, play