Visitors to public science festivals have a tremendous amount of free choice to decide how to navigate through the festival, as well as when, where, and how long to stop at an exhibit. This study examines how elementary-aged children individually or collaboratively engaged with festival exhibits at a public science festival in St. Petersburg, Florida. Although many exhibit activities are designed to appeal to children, no research has been done with regard to child engagement with one-day, outdoor science festivals, such as this one. Engagement can be measured by unobtrusive observation of the behavior and interactions of children. Factors that influenced child engagement in a free-choice learning environment included attention capacity and goals (e.g. engage with exhibits, explore the ambient environment, eat lunch), the ability to interact with peers and adults during their engagement, and the ability to make choices about engaging in collaborative activities or independent free play.