This publication contains a review of trends in research over the past decade followed by 24 studies focusing on cognitive structure, instructional strategies, curricular issues, and attitudes. Among the specific areas investigated are: concept maps as reflectors of conceptual understanding; equations, translations, and number skills in learning chemical stoichiometry; responses to diagnostic, multiple-choice, physics items; children's explanations of natural phenomena; reading and the science learner; students' understanding of space, velocity, and acceleration; student beliefs about place value and decimals; beginning student teachers' opinions about teaching primary science; teacher behaviors and student task involvement within small group and individual activity settings; cognitive preferences and chemistry achievement; investigatory learning in elementary school science; hands-on science program for the intellectually immature high school student; implications of research on alternative frameworks for science teacher education; dimensions of cognitive demand; attainment of an attitudinal objective (belief in the value of community and personal health); arrows in science diagrams; origin and development of the modern science textbook; and use of a repertory grid technique to analyze students' reactions to science. Each study includes rationale, methodology, results, and conclusions. (JN)