Unique contribution of intelligence fluid and crystallized from academic performance

The investment theory of Cattell states that fluid intelligence (Gf) is the basis of crystallized intelligence (Gc), as does the acquisition of skills and knowledge possible. However, the empirical evidence is inconclusive. This research trying to determine the unique contribution of intelligence, Gf and Gc, on the academic performance of school children. A sample of 100 children was used as selection criteria in two types of education: children with scores bad and regular school subjects (regular education) and children with mild mental retardation (special education). Intellectual tests were: Intellectual Ability Scale and Verbal Analogy test. Academic tasks were: reading fluency and math fluency. The resulted showed strong correlations between academic and intellectual variables. The hierarchical regression indicated significant contribution of Gc (Verbal Analogy) to predict the development of reading when the effect of Gf (Intellectual Ability Scale) is controlled. By contrast, Gf showed a significant contribution to explain the performance of mathematics when Gc controls.