Objectives: We examined whether certain characteristics of the social and physical environment influence a child's mode of travel between home and school. Methods: Students aged 11 to 13 years from 21 schools throughout London, Ontario, answered questions from a travel behavior survey. A geographic information system linked survey responses for 614 students who lived within 1 mile of school to data on social and physical characteristics of environments around the home and school. Logistic regression analysis was used to test the influence of environmental factors on mode of travel (motorized vs "active") to and from school. Results: Over 62% of students walked or biked to school, and 72% from school to home. The likelihood of walking or biking to school was positively associated with shorter trips, male gender, higher land use mix, and presence of street trees. Active travel from school to home was also associated with lower residential densities and lower neighborhood incomes. Conclusions: Our findings demonstrate that active travel is associated with environmental characteristics and suggest that school planners should consider these factors when siting schools in order to promote increased physical activity among students.