Aims to quantify the models that 13- and 14 year-old students hold about the causes of the greenhouse effect and ozone layer depletion. Assesses the prevalence of those ideas that link the two phenomena. Twice as many students think that holes in the ozone layer cause the greenhouse effect than think the greenhouse effect causes ozone depletion.…

Reports on a study that addresses the implications of instructional strategies that are used to create cognitive disequilibrations to achieve conceptual change. Discusses several difficulties in the application of such conceptual change strategies. Contains 31 references. (DDR)

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…

Uses interviews and a written questionnaire to probe students' ideas on the origin of earth and life on earth. A significant number of commonly held misconceptions were prevalent in the sample (N=493). Provides guidelines to assist learners in challenging existing views. Contains 64 references. (DDR)

Explores both the qualitative and quantitative dimensions of pupils' ideas related to conservation during state changes of water. Analysis of questionnaire data indicates that qualitative understanding precedes quantitative. Contains 18 references. (DDR)