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Adaptive Instruction for Teacher Education: Inclusive Approaches, Resources and Technology
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Intellectual Exceptionality:

Moderate to Severe Developmental Disability (D.D.)


Ministry Definition... A severe disorder characterized by:

  • An inability to profit from a special education program for student with mild intellectual disabilities, because of slow intellectual development;
  • An ability to profit from a special educational program designed to accommodate slow intellectual  development;
  • A limited potential for academic learning, independent social adjustment and economic self-support. D.D.


  • The identification of students with this exceptionality, Intellectual Exceptionality- DD, like the gifted, is usually based on the results of a psycho-educational assessment and the IQ scores obtained in these assessments.  Students identified as DD obtain very low scores on such tests, and in some cases it may even be difficult or impossible to complete an assessment. 
  • Students with moderate to severe intellectual developmental disabilities are usually identified long before they even enter school.  Sometimes children are identified at birth, or most are identified by the time they are a year to 18 months old, when parents become concerned that their child is not achieving the same developmental milestones in muscle, language or intellectual development as their peers. 
  • Less than 1% of the school population identified as severely developmentally delayed.
  • Placement of students with developmental delays will depend on the severity of the disability and the Special Education Plan of the Board of Education.
  • Most school boards operate self-contained programs for student with severe developmental disabilities and are taught by teachers who have obtained  additional qualifications in special education.  Teaching will be highly individualized but may focus on basic life skills. 


To Do

  • Students with severe developmental delays require highly specialized teaching and extensive use of adaptive technology. When you explore the adaptive technology think of how some of these programs my assist these students.

  • In addition if during your practicum you are in a school that has program for DD go and 'visit' this program.