Teachers of 9 and 10 year olds were found to use varied versions of lessons that increase conceptual understanding. Their effectiveness in supporting conceptual understanding was compared experimentally. Findings and implications for science teaching are discussed. (Author/DKM)

Describes a study that was designed to apply the learning hierarchy paradigm in an instructional unit in high school biology. Findings indicated that regardless of the pupils' sex or the type of school, students taught the hierarchically organized learning task achieved significantly higher than students whose learning task was not hierarchically…