Research evidence indicates that one important variable in learning or development is the degree of match between relevant learner and environment characteristics. It has been argued that, to provide learning environments that would match student characteristics, teachers should be able to understand and identify the relevant characteristics of students and of the learning environment and then learn to provide an environment to match student characteristics in ways that would promote desired behavior. There is a need to understand the nature of the differences between what children or adolescents will respond to in the environment. Such understanding has been enhanced by recent research and theory in developmental psychology. A good description has been provided of the nature of important changes that occur during the school years and how these changes relate to some salient characteristics of children's and adolescents' perceptions of and responses to various aspects of their environment. A synthesis is presented of research findings on developmental stages (late pre-operational thought, early concrete operations, late concrete operations, early formal operations, late formal operations) and teacher effectiveness. Implications for the content of teacher education programs are discussed. (JD)