Constructing causal mechanistic explanations of observable phenomena is a key science practice that is often challenging for students as most mechanisms involve interactions of unobservable entities and activities. In this study, we examined how gesturing with a computer simulation that depicts the molecular mechanism of thermal conduction…

In science education, representations are necessary inter alia for the understanding of relationships between structures and systems. However, several studies have identified difficulties of students when working with representations. In the present study, we investigated students' responses (regarding their preference, test performance, mental…

This article describes revisions to four of the eight constructs of the Duncan molecular genetics learning progression [Duncan, Rogat, & Yarden, (2009)]. As learning progressions remain hypothetical models until validated by multiple rounds of empirical studies, these revisions are an important step toward validating the progression. Our…

Understanding the energy changes that occur as atoms and molecules interact forms the foundation for understanding the macroscopic energy changes that accompany chemical processes. In order to identify ways to scaffold students' understanding of the connections between atomic-molecular and macroscopic energy perspectives, we conducted a…

The connection between the molecular-level structure of a substance and its macroscopic properties is a fundamental concept in chemistry. Students in college-level general and organic chemistry courses were interviewed to investigate how they used structure-property relationships to predict properties such as melting and boiling points. Although…

In this article we apply a novel analytical framework to explore students' difficulties in understanding molecular genetics--a domain that is particularly challenging to learn. Our analytical framework posits that reasoning in molecular genetics entails mapping across ontologically distinct levels--an information level containing the genetic…

The objective of this study was to examine middle school students' developing understanding of the nature of matter and to compare middle school students' ideas to those of elementary schools students, as was done by Nakhleh and Samarapungavan ["J Res Sci Teach" 36(7):777-805, 1999]. Nine middle school students were interviewed using a scripted,…

Our main goal in this study was to explore whether the use of models in molecular genetics instruction in high school can contribute to students' understanding of concepts and processes in genetics. Three comparable groups of 11th and 12th graders participated: The control group (116 students) was taught in the traditional lecture format, while…

The present study makes use of the capabilities of computerized environments to enable simultaneous display of molecular representations that correspond to observations at the macroscopic level. This study questions the immediate and long-term effects of using a multimedia instructional unit that integrates the macroscopic, symbolic, and molecular…