A series of investigations which simultaneously manipulated parameters of reinforcement and age and sex of children were conducted in order to further describe the learning process in children. In addition, an attempt was made to relate perceived parental discipline to performance in the discrimination learning tasks employed in this research. The overall findings of this research, while complex, were that children perform better for punishment for incorrect choices, whether verbal ("wrong") or material (response cost), than for reinforcement for correct responses, whether verbal ("right") or material (token). In addition, the effect of reinforcement and punishment on discrimination learning were found to vary both with the age and sex of the child and the sex of the reinforcing agent. No relationship was found between perceived parental discipline and performance. (Author/LAA)