Using 48 educable mentally handicapped students (ages 12-18) as subjects, a study investigated the effect of prompted and trial-and-error procedures on the learning of a paired-associate task, when items (concrete nouns of less than six letters) in one list were drawn from the same categories (animals, food) and in a second list, from different…

Thirty-seven normal and 33 gifted children from kindergarten classes and 26 retarded children from special classes with mean mental ages of 76 months, 80 months, and 72 months respectively, were initially tested for their understanding of the terms more, same, and less. All who had failed conservation of substance pretests using juice, sand, clay,…