A major focus of the psychology of instruction is understanding and facilitating the changes in cognition and performance that occur as an individual moves from low to higher competence in a domain of knowledge and skill. A new program of research which examines the initial state of the learner as a component of this transition in competence is described in this 8-part document. Part 1 introduces two previous attempts to relate aptitude to instruction: differential aptitude tests and aptitude treatment interaction. Part 2 provides an overview of the two general research approaches to aptitude analysis, the cognitive correlates approach and the cognitive components approach. The approach taken in the present research effort is described as a task analytic approach that considers basic processes, executive strategies, and content knowledge in aptitude test performances of skilled and less skilled individuals. Part 3 considers the relationship between inductive reasoning and general ability. Common generic properties of inductive tasks are discussed as are different types of inductive items on aptitude tests. Part 4 outlines earlier theories on analogical reasoning performance. Problem features, processing models, item processing data and theory, item errors, and performance are analyzed for figural, numerical, and verbal analogy solutions in parts 5 through 7. A final part discusses results of research, concluding that a number of interrelated factors differentiate high and low skill individuals. These factors include management of memory load, organization of an appropriate knowledge base, and procedural knowledge of task constraints. (LP)