Understanding Students · 5 min read
Characteristics of Students with Disabilities
The IDEA Disability Categories
The Individuals with Disabilities Education Act (IDEA) defines 13 disability categories for students ages 3 through 21. To be eligible, a student must have a disability in one of these categories and, because of that disability, need specially designed instruction. A student’s educational needs, not the label, drive programming decisions.
| Category | Key features of the federal definition |
|---|---|
| Autism | Developmental disability significantly affecting verbal and nonverbal communication and social interaction, generally evident before age 3; repetitive activities, resistance to change, unusual sensory responses |
| Deaf-blindness | Concomitant hearing and visual impairments causing needs that cannot be met in programs solely for deafness or blindness |
| Deafness | Hearing impairment so severe that the child cannot process linguistic information through hearing, with or without amplification |
| Emotional disability (federal term: emotional disturbance) | Over a long period and to a marked degree: inability to learn not explained by intellectual, sensory, or health factors; inability to build or maintain relationships; inappropriate behavior or feelings under normal circumstances; pervasive unhappiness or depression; physical symptoms or fears associated with school problems |
| Hearing impairment | Permanent or fluctuating hearing loss that adversely affects educational performance but is not deafness |
| Intellectual disability | Significantly subaverage general intellectual functioning with concurrent deficits in adaptive behavior, manifested during the developmental period |
| Multiple disabilities | Concomitant impairments (e.g., intellectual disability with orthopedic impairment) whose combination causes severe needs; does not include deaf-blindness |
| Orthopedic impairment | Severe orthopedic impairment, e.g., from congenital anomaly, disease such as poliomyelitis, or other causes such as cerebral palsy and amputations |
| Other health impairment (OHI) | Limited strength, vitality, or alertness, including heightened alertness to environmental stimuli, due to chronic or acute health problems such as ADHD, asthma, diabetes, epilepsy, sickle cell anemia, or Tourette syndrome |
| Specific learning disability (SLD) | Disorder in basic psychological processes involved in understanding or using language, shown in listening, thinking, speaking, reading, writing, spelling, or math; includes dyslexia; excludes problems primarily caused by sensory or motor disabilities, intellectual disability, emotional disability, or environmental, cultural, or economic disadvantage |
| Speech or language impairment | Communication disorder such as stuttering, impaired articulation, language impairment, or voice impairment |
| Traumatic brain injury (TBI) | Acquired injury caused by an external physical force (open or closed head injury); not congenital, degenerative, or birth-trauma injuries |
| Visual impairment, including blindness | Impairment in vision that, even with correction, adversely affects educational performance |
Developmental delay is an optional category that states may use for young children. Illinois uses it for children ages 3 through 9 who show delays in physical, cognitive, communication, social-emotional, or adaptive development, which avoids premature labeling.
Two-Part Eligibility Test
Having a disability does not by itself make a student eligible. The disability must adversely affect educational performance so that the student needs specially designed instruction. A student with a disability who needs only accommodations may qualify for a Section 504 plan instead.High-Incidence Disabilities
High-incidence disabilities are those identified most often in schools: specific learning disabilities, speech or language impairments, other health impairments (including ADHD), mild intellectual disability, and emotional disability. Many of these students spend most of the day in general education classrooms.
| Disability | Typical characteristics | Instructional implications |
|---|---|---|
| Specific learning disability | Average or above-average intelligence with unexpected underachievement; deficits in phonological processing, working memory, processing speed, or executive function | Explicit, systematic instruction in the area of deficit; strategy instruction; accommodations for access |
| Dyslexia (reading) | Difficulty with accurate and fluent word recognition, decoding, and spelling, rooted in phonological processing | Structured literacy: systematic phonics, phonemic awareness, fluency practice |
| Dyscalculia (math) | Weak number sense, fact retrieval, computation, and mathematical reasoning | Concrete-representational-abstract sequence, explicit strategy instruction |
| Dysgraphia (writing) | Difficulty with handwriting, spelling, and written composition | Handwriting and keyboarding instruction, speech-to-text, planning organizers |
| ADHD (usually under OHI) | Inattentive, hyperactive-impulsive, or combined presentation; difficulty sustaining attention, organizing, and waiting | Structure, movement breaks, chunked tasks, self-monitoring, frequent feedback |
| Mild intellectual disability | IQ about two standard deviations below the mean (roughly 55–70) with adaptive behavior deficits; learns at a slower rate | Concrete, hands-on instruction, many repetitions, explicit generalization |
| Emotional disability | Internalizing (anxiety, depression, withdrawal) or externalizing (aggression, defiance) behaviors that persist over time | Positive behavior supports, social-emotional instruction, consistent structure, mental health collaboration |
Low-Incidence Disabilities
Low-incidence disabilities occur less often and usually require more specialized supports: moderate to severe intellectual disability, autism, sensory impairments, physical disabilities, multiple disabilities, deaf-blindness, and traumatic brain injury.
Moderate to severe intellectual disability
Intensive support across life domains; instruction emphasizes functional academics, communication (often AAC), self-care, daily living, community participation, and vocational preparation.
Autism
Deficits in social communication (reciprocity, nonverbal communication, relationships) and restricted, repetitive behaviors (stereotyped movements, insistence on sameness, fixated interests, sensory sensitivities). Support needs vary widely.
Visual impairment
Blindness or low vision. Needs may include orientation and mobility instruction, braille or large print, audio materials, assistive technology, and instruction in compensatory skills; students miss incidental visual learning.
Hearing impairment
Varies by degree (mild to profound), type (conductive, sensorineural, mixed), and onset (prelingual or postlingual). Approaches include oral/aural, manual (ASL), and total communication; attend to acoustics and visual access.
Physical disabilities
Cerebral palsy, spina bifida, muscular dystrophy, limb differences. Address physical access, adapted materials and equipment, personal care, fatigue, and health needs.
Traumatic brain injury
Effects depend on location and severity: attention, memory, processing speed, executive function, motor skills, fatigue, and behavior changes. Recovery is individual and can continue for years, so plans need frequent review.
The Impact of Disabilities on Learning
| Area affected | Effect on learning |
|---|---|
| Cognitive processing | Attention, memory, processing speed, and executive function limit how much information is taken in, organized, and retrieved |
| Sensory access | Vision or hearing loss limits access to information most students gain incidentally |
| Motor function | Limits interaction with materials, writing, and movement through the environment |
| Communication | Limits participation in verbal instruction and the ability to show what is known |
| Social-emotional functioning | Affects engagement, motivation, and the relationships that support learning |
Students may also show secondary effects: learned helplessness after repeated failure, low self-esteem, social isolation, and behavior problems. Teachers address both the primary disability and these secondary effects.
Key Concept
Disability interacts with culture, language, family income, interests, and strengths. Effective instruction builds on strengths, avoids assumptions based on labels, and keeps expectations high while providing appropriate supports.Finished reading?
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