Farm to School programs (FTS) have proliferated since the first FTS pilot projects in 1996-1997 (National FTS Network 2011). Research surrounding FTS programs has focused on quantifying the potential benefits for local economies and students' nutrition, while little research has addressed factors that influence a school's decision to participate in a FTS program. FTS is often narrowly defined as the use of local foods by the school. However, the extent of local food inclusion alters the local economic stimulus generated by the program and may also alter school meal participation by students and support by parents. In this study, we follow the USDA's Farm to School Census approach and define FTS as any promotion of local foods or school gardens including field trips to farms, maintenance of a school garden, taste tests, and other curriculum or promotional components. We also recognize that a school's decision to participate depends heavily on the supply of and types of farms in the area, so we take supply-side factors into account. In addition to simple binary FTS participation, we assess what factors are associated with the intensity of participation, the types of FTS activities implemented, and the challenges faced by participating and non-participating schools. The results provide a nuanced understanding of FTS participation. Our models are estimated using data from the USDA's Farm to School Census(2014), the USDA's Census of Agriculture (2012)and the USDA's database of farmers'markets (2015). We find factors that influence the FTS decision include the supply of local food, school size, percent of students on free or reduced cost meals, federal reimbursements for the cafeteria programs, total school system expenditures, food cost, cafeteria sales, county population, race composition and urbanicity. The results suggest that both school characteristics and local farm production factors may influence FTS participation. The results will be useful in informing policy as well as providing insight into the nature of FTS programs for future studies of FTS benefits.