Inclusion and Students with Intellectual Disabilities: History
Please note this is an old version of this entry, which may differ significantly from the current revision.

Individuals with intellectual disabilities (ID) have the same right to participate in the general education curriculum as their typically developing peers. Inclusion is the belief that all individuals with diverse needs may participate in society.  In schools, inclusion implies acceptance of differences and access to the the general education curriculum and environmnet. Students with more severe cognitive disabilities and daily living skill needs called intellectual disabilities (ID) can be successful in the inclusive classroom with appropriate supports and services.  For individuals with ID in general education classrooms, inclusion in the general education setting is critical to their long-term participation in the community, improved academic and behavioral performance, and has been associated with positive health and well-being.

  • inclusion
  • intellectual disabilities
  • co-teaching
  • evidence-based practices

1. Challenges of Including Individuals with Intellectual Disabilities

Even with the sound belief and strong argument for the inclusion of individuals with disabilities, including federal laws, many teachers are still anxious about including students with ID in the general education setting as they must navigate two major and seemingly contradictory pushes from education systems: equity versus excellence [1][2]. Inclusion is more than just an educational setting; it is an opportunity to succeed with appropriate supports and services. Equity and access do not automatically translate to growth and success. One of the greatest challenges that educators and administrators face includes the meaningful integration into an increasingly advanced general education curriculum, while simultaneously meeting the physical, emotional, behavioral, and social needs of students with ID. The disparities between the typical student and the student with ID become greater as they progress into adolescence, making meaningful inclusion even more challenging at the secondary level [3][4][5]. Social engagement in inclusive settings can also be more difficult at the secondary level, as adolescents are sensitive about self-image and identity and may not want to interact with those whom they feel are different [6].
This is not the only challenge facing teachers and administrators. Teacher preparation programs often do not focus on preparing all future teachers to work with students who struggle academically. The emphasis in teacher preparation programs is on content, not students. High-stakes testing and accountability may increase the stress and anxiety of teachers working in an inclusive classroom with individuals with ID [1][7][8]. Limited planning time and lack of collaboration with professionals remain some of the greatest challenges to effective inclusion [9]. The success of an inclusive program also hinges on the knowledge and attitude of the teacher, and negative perspectives about inclusive education have a direct impact on the lack of success [10]. Although numerous studies conducted over many decades have determined that teachers value students with disabilities in the inclusive setting, they remain apprehensive to teach them in the general education classroom because of concerns related to preparation and support [2][11].
One critical factor in the success of students with disabilities who are included in the general education classroom is the philosophy of the teachers and administration. Teacher attitudes and beliefs have a direct impact on students’ performances [12]. Educators must first believe that all children have the potential to learn and be willing to create supportive inclusive opportunities. Identifying student strengths and developing strategies to support instructional goals is imperative. Evidence-based practices (EBPs) can be shared to help teachers and their students with ID succeed in the inclusive setting. Professional development is important in ensuring that teachers feel prepared to meet diverse student needs. Unfortunately, even with a positive attitude towards the inclusion of students with disabilities in the classroom, teachers may still have concerns about their ability to support students with disabilities, and this often impacts their confidence and willingness to serve these students in the general education classroom [9].
However, with effective knowledge and understanding of EBPs for students with ID, we can better prepare and equip teachers to meet the diverse needs of students with ID in their classrooms, as well as to improve their perceptions of inclusion and their confidence in their own abilities. According to Pearce and Forlin [1], the four main components of effective inclusive practice include the following: (1) Knowledge of the child; (2) Understanding the implications of the disability; (3) Knowledge of evidence-based strategies and appropriate accommodations; and (4) Knowledge of adaptations and interventions. To alleviate teacher concerns about effectively addressing the needs of students with ID in the inclusive classroom as well as to improve teacher perceptions, Buntinx and Schalock [13] stressed the importance of shifting the focus from assessing individual deficits to identifying helpful supports instead. Research-based recommendations shared by Räty et al. [14] support individuals with ID in the inclusive setting by identifying strategies to support academic and behavioral goals, as well as life skills and communication. These research-based strategies enable teachers to provide meaningful inclusive instruction. Evidence-based practices for severe intellectual disabilities include systematic instruction and the use of picture prompts during reading. For mathematics, systematic instruction has a research-based level of high effectiveness, along with increased wait time for students to recall answers and participate. Community-based instruction has also been proven successful, along with picture schedules, social skills, task analysis, and video/visual supports as accommodations [15]. Systematic instruction has also been noted as very effective, especially in promoting social inclusion and developing self-determination [16].

2. Inclusion and Intellectual Disabilities

The 21st century has seen increased attention to the diversity, equity, and inclusion movement, identifying and addressing acceptance of marginalized groups of gender, religion, race, ethnicity, sexuality, and disability. Worldwide organizations including the World Health Organization and the United Nations Convention on the Rights of People with Disabilities (CRPD) have focused on the importance of inclusive practices in education which led to positive outcomes for individuals including economic opportunities, quality of life, and the safeguarding of basic human rights [3]. In the United States, according to federal law, the American Individuals with Disability Act 2004 and Public Law 114-95, and the Every Student Succeeds Act 2015, congress states, “Disability is a natural part of the human experience and in no way diminishes the right of individuals to participate in or contribute to society. Improving educational results for children with disabilities is an essential element of our national policy of ensuring equality of opportunity, full participation, independent living, and economic self-sufficiency for individuals with disabilities” [17].
The concept of inclusion in education refers to the integration of individuals with disabilities into the general education or mainstream curriculum. Individuals with mild disabilities such as learning disabilities are most often included in the general education setting with supports and services provided for success.
In 1989, only 27% of students with disabilities were in the regular education classroom. In 2019, 65% of students with disabilities were in regular education, an increase of 35%, but the numbers of those with intellectual disabilities continue to lag far behind those with milder needs [18][19].
Currently, the majority of the American students participating in the inclusive setting have mild to moderate cognitive disabilities such as specific learning disabilities. However, with the increase in all SWD who are included in the general education classroom, there has also been an increase in inclusive placements for individuals with more severe cognitive disabilities, specifically, those with intellectual disabilities (ID). Intellectual disabilities are defined as “…significant limitations both in intellectual functioning and adaptive behavior as expressed in conceptual, social, and practical adaptive skills” [20]. Severe cognitive disabilities typically include students with ID. These students are described as having an IQ of 70 or lower, with at least two deficits in adaptive behavior. An individual with deficits in adaptive behavior may struggle with daily living skills, such as dressing and bathing. This population of students with ID was also previously not included at all in the general education classroom; however, currently, 45% of students with ID are included in general education settings for 40% of the day or more [21] as compared to only 10% included in the regular classroom in 1996 [22].
As families and advocates for individuals with ID continue to be more successful in providing inclusive opportunities both in school as well as in the community, school administrators and teachers can find it challenging to meet the multiple and varied needs of students with more severe ID. In an era of increased accountability for teachers and national standards, trying to meet the needs of students with greater cognitive and behavioral needs in a classroom, where typically functioning students may also struggle to meet new standards, can seem unrealistic and unfair.
Individuals with ID have the same right to participate in the general education curriculum as their typically developing peers. According to the Down Syndrome Association of West Michigan, “Inclusion is a philosophy of education based on the belief in every person’s inherent right to fully participate in society. It implies acceptance of differences and access to the educational experiences that are fundamental to every student’s development” [23]. Inclusion benefits everyone. For individuals with ID in general education classrooms, inclusion in the general education setting is critical to their long-term participation in the community, and has been associated with positive health and well-being for all individuals, including those with ID [24][25]. Further, the benefits of inclusion for students with ID include increased independence and acceptance, as well as the development of academic and social skills, self-advocacy, and the ability to make choices [24][26][27]. Ultimately, exposing individuals with ID to typically developing peers, grade-level curriculum, and appropriate social interactions may result in more authentic friendships and life experiences they can take with them beyond school [28][29]. The benefits of inclusion for students without disabilities are numerous and include improved social/emotional skills in addition to improved academic achievement [30]. Some of these benefits include increased opportunities to build meaningful friendships, an increased appreciation and acceptance of individual differences and diversity, more opportunities to master activities by practicing and teaching others, and an overall increase in academic performance through an increase in resources and more individualized instruction [24][25][30][31][32][33]. Furthermore, there are improved long-term outcomes, because participation in an inclusive classroom setting prepares all students for adult life in an inclusive society.

This entry is adapted from the peer-reviewed paper 10.3390/educsci13060558


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