Food selectivity is a common problem among children and youth who have intellectual and developmental disabilities or autism spectrum disorders. Whereas most intervention research has been conducted under simulated conditions in clinic and hospital settings, this study evaluated teacher implemented procedures at a specialized school. The participant was an adolescent girl who had autism, chronic food selectivity, and disruptive mealtime behavior. Before intervention, she ate a restrictive diet comprised primarily of "crunchy" foods. During intervention, teachers applied paced-prompting, differential positive reinforcement, and demand fading to gradually increase the quantity of novel foods the girl consumed. Her improved consumption maintained seven-months post-intervention. We discuss elements of the intervention plan and a focus on natural-setting feeding research. (Contains 1 figure.)