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…

Powerful online visualizations can make unobservable scientific phenomena visible and improve student understanding. Instead, they often confuse or mislead students. To clarify the impact of molecular visualizations for middle school students we explored three design variations implemented in a Web-based Inquiry Science Environment (WISE) unit on…