Exploring Adaptations of the VisChem Approach: Advancements and Anchors toward Particle-Level Explanations

The Next Generation Science Standards (NGSS) have been imperative for informing many facets of the chemistry education research field, one of which includes the professional development (PD) of high school teachers. While many researchers and practitioners have responded to the NGSS' calls for reform by attending to internal factors that influence the PD's design, resources, and facilitation, there is less attention on extant factors that may negatively affect PD uptake and fidelity. Such factors encompass traditions of teaching chemistry or chemistry-related imprecisions within the NGSS themselves. If left unaddressed, these factors can act as anchors preventing advancements toward students' particle-level explanations and their chemistry conceptual understanding. In this article, we investigate the uptake and fidelity of our own PD program known as the VisChem Institute. The data are comprised of PD participants' learning designs (i.e., lesson plans) collected from the 2020 cohort (N = 20) and the 2021 cohort (N = 15). Results show that, although there was uptake in terms of the particulate level among participants' learning designs, more detail was ascribed to the description of molecular-level species rather than the explanation of relevant processes. Furthermore, an ontological analysis revealed that interpretations of evidence and models for description as well as symbolic heuristics for explanation may account for the VisChem approach's distortion in its translation to participants' learning designs. Implications and recommendations for chemistry instruction and research at both secondary and undergraduate levels are discussed.