Teaching about Intellectual Disabilities/Mental Retardation

Ideas for Classroom Activities

The two activities described below are used in my Exceptional Learners class (Education 203) to teach college students (mostly second-year) about intellectual disabilities/mental retardation. I believe the activities would also be appropriate for use at the high school level, perhaps in a psychology class. Please feel free to utilize these activities and reproduce any of the related materials.

Activity One: Definitions and Terminology

\This activity is used to introduce the topic. I give pairs or trios of students a list of 12 definitions of intellectual disabilities/mental retardation (see the worksheet and chronological list with dates and references). Their task is to:

1) put the definitions in chronological order, beginning with the oldest;

2)  write their best guess regarding the date (year) next to each definition;

3) list (in chronological order) all the terms used in the definitions to refer to mental retardation, and

4) identify at least two trends that they noted in regard to how the definitions have changed throughout the years (for instance, more recent definitions provide more specific criteria for diagnosing mental retardation; they no longer assume permanence or incurability; they avoid reference to causation, "constitutional" or otherwise; and they tend to be more conservative in that they classify fewer individuals as having mental retardation).

Allow 20 to 30 minutes for students to complete these tasks. Ask each pair or trio to choose a spokesperson.

When all pairs or trios are done, I ask the class which definition they think is the oldest and what date they have assigned to it. I also ask what evidence they used in coming to this conclusion. I then write the term used in the definition (idiot), the definitions' number (8), and its date (1255 to 1290) on the board. I repeat this procedure, asking which they think came next, and write the same information on the board, making corrections when necessary and commenting about the origins of each definition. (Generally students can sequence the definitions fairly well, although they sometimes have difficulty with those in the middle)

After we have sequenced and dated all 10 definitions, we talk about how and why terminology has changed. I clarify the fact that intellectual disability is a relatively new term, having recently replaced mental retardation, which was the generally accepted term for more than 40 years. I also explain that the term mentally handicapped was often used during the 1970s and 1980s, but since disability has been substituted for handicap in federal and state laws, mentally handicapped is generally no longer appropriate. (See Speaking and Writing About People with Disabilities for more information)

Finally, I ask about trends regarding changes in the definitions. Depending on the class, they sometimes need a little help in describing, if not recognizing, the trends.

I conclude this activity by explaining the three parts of the current AAMR definition: subaverage intellectual functioning, impaired adaptive behavior, and origination during the developmental period. To help students take notes during this brief presentation, I use a slide titled "Translating the AAIDD Definition" which provides explanatory information.

This entire activity, including the brief presentation on the current AAIDD definition, takes one 70-minute class period. 

Activity Two: Levels of Intellectual Disabilities/Mental Retardation

This activity introduces the topics of levels and characteristics of mental retardation.

I begin the activity by familiarizing students with traditional, IQ-based levels of mental retardation: mild (IQ range 55 -70), moderate (IQ range 40 - 54), severe (IQ range 25 - 39), and profound (below 25) as well as the traditional (though no longer appropriate) special education terminology (educable and trainable mental retardation) and that the two middle levels, moderate and severe, are often considered together. I then explain that the AAMR has now developed  a new classification system based on need for support. Using a PowerPoint slide, I briefly describe these four levels: Intermittent, Limited, Extensive, and Pervasive.

I then divide the students into groups of three or four, distribute the handout,  Three Vignettes (brief case descriptions of individuals at the traditional IQ-based levels of mild, moderate to severe, and profound mental retardation), and explain that assuming the vignettes are representative, they must:

1) develop lists of characteristics of individuals with mild, moderate to severe, and profound mental retardation (one list for each of the three levels) including information on physical appearance, rate of development, causation, academic attainment, and adult functioning;

2) determine the level of support needed by each of the three individuals in the case vignettes.

Allow 20 to 30 minutes for students to complete these tasks. Ask each group to choose a spokesperson.

When all groups are finished, I ask the spokespersons to read their lists. I correct any inaccuracies and based on the students' lists, put composite lists of characteristics for each of the three levels on the board. I also ask the group spokespersons what level of support they believe the individuals in each of the three vignettes would require. I then distribute a handout titled Intellectual Disabilities: Typical Characteristics and ask students to compare their lists of characteristics (and our composite lists) to those on the handout.

I conclude this activity by explaining that although these brief case studies are rather typical, individuals with mental retardation are just that: individuals. Therefore, even within the IQ levels and levels of support, there is a great deal of variation, and the characteristics listed on the board and in the handouts, though typical, are generalizations that do not hold for all individuals with mental retardation.

Activity Two can be completed in one 70-minute class period.

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Last updated 11/9/15
Edmund J. Sass, Ed.D.
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