Background: Across the nation, schools have become actively involved in developing obesity prevention strategies both in classrooms and in cafeterias. We sought to determine the type of foods being offered during lunch in the cafeteria of 3 public high schools in 1 county and if this reflects the purchasing patterns of students. By labeling foods based on nutrient density using a stoplight approach of green, yellow, and red colors, we were able to categorize all foods including the National School Lunch Program (NSLP) and competitive foods available in the cafeteria. Methods: Over a 4-week cycle, daily food purchases were gathered and the proportions of green, yellow, and red foods offered and purchased was compared. Results: Findings from this study suggest that students in these 3 high schools purchased foods in relative proportion to what was available in the school cafeteria for the NSLP. Green and yellow foods included in the NSLP comprised 77% of the offerings and 73% of the purchases. In contrast, 61% of the competitive foods were classified as red foods, and the purchasing of red foods made up 83% of competitive food sales. These results indicate that students purchase foods of minimal nutritional value at greater proportions in the school cafeteria. Conclusions: These results suggest that the nutritional policy for the NSLP promotes the offerings of a wide array of foods. Schools should consider a nutrition policy that regulates the sale of competitive foods. (Contains 3 tables.)