Social Stories™ are a story-based intervention commonly used to teach students with disabilities how to behave in new routines or changing environments, academic skills, and social interactions including tacting others' emotions. According to the National Standards Project, story-based interventions are considered an established treatment. However, the efficacy of Social Stories™ is confounded by limitations in chosen experimental designs, threats to internal validity, and additional interventions within treatment packages. The current study used Social Stories™ to teach classroom social skills to children diagnosed with an intellectual disability. We used a multiple baseline across participants design to evaluate changes in classroom social skills when using Social Stories™. We taught a total of four response classes, including: saying, "please," saying, "thank you," appropriate hand raising, and giving assistance. The results indicate that Social Stories™ may be an effective intervention to increase classroom social skills. This is one of the first studies to evaluate and demonstrate the effectiveness of Social Stories™ as a standalone intervention. The present study also extends the current social studies literature in several areas, such as developing ways to promote generalization and assessing the social validity of the goals, procedures, and outcomes of the study.