The effects and interactions of 3 variables on concept learning and retention were investigated: (1) method of stimulus presentation; (2) learning process; and (3) intellectual ability. One hundred and forty-four (144) 4th graders were divided into 4 groups, each of which was further subdivided into high, middle, and low intellectual ability levels. Each group was presented 3 school-like conceptual tasks to learn and retain. Treatment conditions included different combinations of inductive or deductive concept learning and simultaneous or successive stimulus presentation. Among the results are the following: (1) students, regardless of level of intelligence, learned concepts more effectively under the deductive process; (2) retention was found to be a function of how well a concept is learned and not of how it is learned; (3) mode of stimulus presentation was not found to be a differentiating variable; and (4) higher intellectual level students had higher learning and retention scores than those of lower intellectual levels. (Author/TL)