Visualizing the chemical structure and dynamics of particles has been challenging for many students; therefore, various visualizations and tools have been used in chemistry education. For science educators, it has been important to understand how students visualize and represent particular phenomena--i.e., their mental models-- to design more…

Following up on the effects of learning environments is essential to learning. The aim of this study was to examine students' mental models related to the concepts of expansion and contraction of materials. The population of the case study consisted of 155 students in a city center in Turkey. The data was gathered using open-ended questions that…