A total of 47 pupils enrolled in grades 3-8 was selected for this study. Of these pupils, 17 were from a rural area and 30 were from an urban area. The pupils selected had to (1) be of Mexican descent, (2) be currently enrolled in educable mentally retarded (EMR) classes, and (3) have evidenced a problem in using the English language due to their native language being Spanish. The assessment instrument used was the "Escala de inteligencia Wechsler para ninos," which is the Spanish version of the Wechsler Intelligence Scale for Children." Results of the testing showed that the average gain from the previously low test scores (which classified the students as retarded) to the present test scores was 13.15 IQ points. The median score for the prior IQ was 70, while the median score for present IQ was 83. It was concluded that many Mexican American pupils may have been placed in EMR classes solely on the basis of performance on an invalid IQ test. The previous testing was termed invalid because this particular subpopulation of pupils lacks facility with, and understanding of, the English language. When tested in Spanish, pupil performance in many cases was above the cutoff level of the EMR category (approximate IQ of 75). (LS)