The purpose of this study is to determine whether a walking school bus program can increase the number of children walking to school and decrease the number of children driven by car to school.

Walking to school is associated with higher levels of physical activity, which is an objective of Healthy People 2010. However, parents' concerns about safety have been identified as a barrier that prevents their children from walking to school. A walking school bus (WSB) addresses these concerns by providing a supervised period of physical activity on the way to school. A WSB is a group of children led to and from school by responsible adults who walk together along a set route. The peer-reviewed literature on active travel to school is sparse. We evaluated a WSB program, to test the hypothesis that it would increase the proportion of children walking and decrease the proportion of children driven by car to school.

Comparison: We conducted an 18-month controlled, quasi-experimental trial at three public elementary schools in Seattle, Washington. The intervention school was assigned a WSB coordinator who dedicated 10-15 hours/week establishing WSB routes and implementing school activities on pedestrian safety. Each "bus" had its own set route to school from different locations in the surrounding neighborhoods and was staffed by several parent leaders. The two control schools received standard Seattle Public Schools resources on walking to school including "Safe Route Maps," a traffic and safety committee, and school safety patrols. The primary outcomes were the proportions of children who walked with and without an adult or were driven by car to school. We used the test for independent proportions to compare the proportion of children transported to school at the intervention versus control schools.

Inclusion Criteria:

• Enrolled in school
• Present on the day of the survey at one of 3 study schools.

Exclusion Criteria:

• Absent on the day of the survey at one of 3 study schools.