Background: Many schools were temporarily closed in response to outbreaks of the recently emerged pandemic influenza A/H1N1 virus. The effectiveness of closing schools to reduce transmission depends largely on student/family behavior during the closure. We sought to improve our understanding of these behaviors. Methodology/Principal Findings: To characterize this behavior, we surveyed students in grades 9-12 and parents of students in grades 5-8 about student activities during a weeklong closure of a school during the first months after the disease emerged. We found significant interaction with the community and other students-though less interaction with other students than during school-with the level of interaction increasing with grade. Conclusions: Our results are useful for the future design of social distancing policies and to improving the ability of modeling studies to accurately predict their impact.