Over 42 million meals--31.2 million lunches and 11 million breakfasts--were served on a typical school day in fiscal year 2009 to children through USDA's National School Lunch and School Breakfast Programs. School food authorities (SFAs) operate local school feeding programs and deliver the meals to the schools. SFAs must serve appealing, healthful meals while covering food, labor, and other operating costs, a challenge that may be more difficult for some SFAs than for others due to differences in costs per meal across locations. Analysis of data on school costs per meal from a large, nationally representative sample reveals that geographic variation is important. In the 2002-03 school year, SFAs in the Southwestern United States had, on average, consistently lower foodservice costs per meal than did SFAs in other regions. Urban locations had lower costs per meal than did their rural and suburban counterparts. Wage and benefit rates, food expenditures per meal, and SFA characteristics such as the mix of breakfasts and lunches served each contributed to the differences in foodservice costs per meal across locations. The importance of these factors varied by location. Appendices include: (1) The Model and Model Diagnostics; and (2) School Breakfast. (Contains 10 tables, 6 figures and 18 footnotes.) [For the associated report, "School Foodservice Costs: Location Matters. ERS Report Summary," see ED521221.]