Describes a study that explores the instructional influence of presenting pictures at the molecular level when introducing chemistry concepts and solving chemistry problems. Explores the effect of the pictures on students' conceptions and problem-solving abilities. Contains 59 references. (DDR)

Reports on a study designed to examine the effect of concrete and formal instruction upon reasoning and science achievement of sixth grade students. Results indicated that the concrete instruction group had significantly higher levels of performance in science achievement and cognitive development and that males outperformed females. (TW)