This is a mix methods follow-up study in which we reconfirm the findings from an earlier study [Vedder-Weiss & Fortus [2011] "Journal of Research in Science Teaching, 48(2)", 199-216]. The findings indicate that adolescents' declining motivation to learn science, which was found in many previous studies [Galton [2009] "Moving to…

Previously, a small scale, interview-based, 3-year longitudinal study (ages 11-14) in one school had suggested a learning progression related to the concept of a substance. This article presents the results of a large-scale, cross-sectional study which used Rasch modeling to test the hypothesis of the learning progression. Data were collected from…

This longitudinal study investigated the progression in junior high school (JHS) students' conceptions of the structure of matter while studying a new instructional approach dealing with "Materials." In particular, we studied the progression of students' learning along two dimensions: (a) the conceptual model; and (b) the context of application.…