The American Association on Intellectual and Developmental Disabilities defines intellectual disability as "...characterized by significant limitations both in intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills. This disability originates before the age of 18." This is similar to the Individuals With Disabilities Education Act definition (see Intellectual Disability, IDEA). Adaptive behavior domains include communication, self-care and social skills. Until Rosa's Law was enacted in 2010, the term "mental retardation" was used in Individuals With Disabilities Education Act and by some states. The change to intellectual disability represents, for many, a paradigm shift that emphasizes the fit between a student's capacities and the demands placed on them, as well as the supports the student requires for self-determination.
The Individuals With Disabilities Education Act 2011 federal child count reported 434,572 children ages 3 through 21 identified with intellectual disabilities, a decrease of 22 percent since 2005. Males are more frequently identified than females and children from under-represented populations and from families with low socioeconomic status are more likely to be identified than their white peers.
Students identified with intellectual disabilities demonstrate limited educational achievement. Only a small percentage enrolls in post-secondary education programs. Employment is low, with only 31 percent employed three years after leaving high school. Wages were generally low suggesting that this population may be underemployed. Relatively low rates of community participation and independent living were also reported.
Educational programs for students with intellectual disabilities have historically emphasized functional skill development and were often provided in segregated special education settings. While many believe functional skills are important, data increasingly suggests that students with intellectual disabilities demonstrate improved academic achievement when provided quality instruction using general education curricular materials in the general education classroom. Similarly, data suggests that students with intellectual disabilities can be successful in post-secondary education settings. The U.S. Department of Education's Office of Post-Secondary Education has established the Transition Programs for Students with Intellectual Disabilities to promote enrollment.
Evidence-based practices for students with intellectual disabilities include applied behavior analysis, instructional matching, functional communication and self-management strategies. Universal design for learning principles and incorporating assistive technology (computer-based learning, tablets and video game consoles) are also being promoted. Effective secondary transition planning is critical.