Research on the development of ability to control variables during adolescence is reviewed. The first section discusses studies by Piaget and his collaborators, replications of Piaget's studies, and related studies by other investigators. Factors which influence performance on controlling variables tasks are delineated; the existence of Piaget's…

Common misconceptions of children that may interfere with their learning science are discussed, including three aspects of science programs: complexity, fragility, and unclear learning outcomes. Special attention is given to the Science Curriculum Improvement Study (SCIS). Methods for solving problems dealing with students' misconceptions are then…