Assessments associated with learning progressions are designed to provide diagnostic information about the level and nature of student understanding. Valid interpretations of such diagnoses are only possible when students consistently express the ideas associated with a single learning progression level. Latent class analysis was employed to…

According to Piaget's theory, maturation of the nervous system is sufficient for the development of formal thought. If this were the case, the job of the educational system would be small indeed. Rather, maturation determines only the totality of possibilities and impossibilities at a given stage. This study investigates whether instructional…