Intellectual disabilities are defined by significantly below average intellectual functioning and deficits in adaptive behaviors that manifest during development and adversely affect educational performance. Students are identified based on levels of support needed, with eligibility criteria including intellectual functioning scores more than two standard deviations below average, deficits in adaptive behaviors, and low academic achievement. Effective educational practices for students with intellectual disabilities include a functional curriculum, adaptations, direct instruction of academic and social skills, hands-on learning, assistive technology, and peer tutoring.