Policymakers in many countries, including the United States, United Kingdom, and Australia, have introduced programs to increase walking and biking to school through education, encouragement, and infrastructure improvements. The U.S. government has allocated over $1.1 billion to the federal Safe Routes to School program since 2005. However, there are few evaluations of the Safe Routes to School program. Our study used a robust quasi-experimental research design to measure the impacts of Eugene, Oregon’s Safe Routes to School program on walking and biking. Using data collected between 2007 and 2011 at 14 schools with and without Safe Routes to School programs, we showed that the Safe Routes to School program was associated with increases in walking and biking. Education and encouragement programs were associated with a five percentage point increase in biking. Augmenting education programs with additional SRTS improvements such as sidewalks, crosswalks, covered bike parking, and Boltage was associated with increases in walking and biking of five to 20 percentage points. The study results illustrate the potential for the Safe Routes to School program to change behavior and should encourage other communities to plan for multi-modal school travel.