This study investigates the progression of students' meaning-making of epigenetic phenomena while discussing multiple visual representations depicted at different levels of biological organization. Semi-structured focus group sessions involving ninth-grade students (aged 15-16) from a Swedish lower secondary school were video recorded. Students'…

Teacher professional learning plays a critical role in education reform by enabling teachers to refine their professional skills and keep up with changing content knowledge, pedagogy, and trends in schooling. This study examines how and under what conditions principal instructional leadership contributes to teachers' professional learning in…

The present study tested the possibility of operationalizing levels of knowledge acquisition based on Vygotsky's theory of cognitive growth. An assessment tool (SAM-Math) was developed to capture a hypothesized hierarchical structure of mathematical knowledge consisting of procedural, conceptual, and functional levels. In Study 1, SAM-Math was…

Many latent traits in the human sciences have a hierarchical structure. This study aimed to develop a new class of higher order item response theory models for hierarchical latent traits that are flexible in accommodating both dichotomous and polytomous items, to estimate both item and person parameters jointly, to allow users to specify…