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An exploratory study compared 49 educable retardates with 20 third and 19 sixth grade normal children on measures of locus of control, level of aspiration, and n-Achievement. The results were consistent with a developmental progression, sixth graders scoring more internal in locus of control and more realistic in level of aspiration than third graders. The retardates who were chronologically older than the sixth graders tended to resemble third graders on these various measures.
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Riedel et al. (1970) studied this question.
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