The present study was designed to ex amine the effectiveness of Feuerstein's Instrumental Enrich ment program in improving the cognitive performance of educationally retarded adolescents in vocational secondary schools. Five experimental and four control class groups took part in the one-year study. The experimental classes were instructed using the instrumental enrichment program by their specially trained regular teachers for approximately 45 minutes per day, 3 to 5 days per week, while the control group classes spent equivalent time in contact with their own teachers in the course of their usual program. Pre-post test analysis revealed significant effects of the FIE program on the cognitive performance of the experimental class students when compared with controls. As early as 1956, severe doubt was being expressed . as to the validity of the concept of primary genetic control over intellectual performances (Ferguson, 1956). This early expression of doubt heralded a controversy that had yet to begin in earnest, a controversy that is still raging many years later. Respected behavioral scientists (e.g., Burt, 1940; Herrnstein, 1973; Jensen, 1969, 1973; Spearman, 1927) had long argued that psychometrically measured lack of intellectual capacity, and the associated cognitive deficits usually seen or inferred, were in the main a biological given. However, there is a dawning suspicion?even among geneticists?that many people who fail to show cognitive or intellectual ability may not be irrevocably disabled but, rather, may be displaying the results of an unsuitable or unfortunate developmental process (Dobzhansky, 1973; McClearn, 1964, 1970; Vale & Vale, 1969). A growing number of authors have begun to point to performances in those people designated to be intellectually or mentally deficient that do not square with the common concep tion of the types of problems such people should (or should not) be able to solve (Bernstein, 1960, 1961; Clarke & Clarke, 1973; de Bono, 1970, 1973, 1976; Dunn, 1968; Feuerstein, 1970, 1979; Feuerstein & Richelle, 1963; Riessman, 1962; Robinson & Robin son, 1970; Rowher & Ammon, 1971; Sarason & Doris, 1969; Schwebel, 1967, 1968; Vygotsky, 1962). Thus, it can be fairly stated that the experts still disagree as to the extent to which intellectual capacity (or thinking or problem-solving ability) is biologically determined and, therefore, they disagree regarding the extent to which cognitive functioning may be positively or negatively influenced by one's environment. Of late, those favoring the importance of en vironmental influences, and the related possibility of reversing poor cognitive development, have been somewhat more vocal. Several have put forth pro grams for improving the thinking skills and, ulti mately, the intellectual capacity of those who are often regarded as irreversibly slow learners and thinkers (de Bono, 1970, 1973, 1976; Feuerstein, 1980; Weber, 1974). While there are many points of theoretical agreement and some similarities in methodology among these authors, Feuerstein and his colleagues ap pear to have developed the broadest, most theoretical and practically developed system of intervention in order to improve cognitive functioning when it has not developed well on a natural basis. Feuerstein's system includes theoretical analysis, a broad range of remedial materials and techniques, and a definite method for training front-line teaching and support personnel. Feuerstein argues that slow thinking and learning, and subsequently retarded performance, arise because of the failure of nurturing adults to provide adequate mediated learning experience during the crucial years of development (Feuerstein, 1979, 1980; Feuer stein & Rand, 1974). This argument is presented predominantly on the basis of work done with Address correspondence to Mary Waksman, Faculty of Education, University of Toronto, 371 Bloor St., West, Toronto, Ontario, Canada M5S 2R7. This content downloaded from 207.46.13.113 on Thu, 06 Oct 2016 04:25:26 UTC All use subject to http://about.jstor.org/terms