Magnetism as a size dependent property: a cognitive sequence for learning about magnetism as an introduction to nanoscale science for middle and high school students

In this study, we use evidence from students in grades 10--12 (N = 148) to document the ways in which children learn about and model their conceptual understanding of magnetism. Our model-based design capitalizes on phenomena that are engaging to students, to describe the behavior of magnetic materials across scale, from the familiar to the nanoscale. Data are drawn from written responses to pre- and post-questionnaires, embedded assessments, activity journal pages, and informal interviews, to describe a progression of students' mental models of magnetism. Our goal is to integrate multiple related concepts to describe possible pathways for learning. An implication of this work is that it may be used to inform level-appropriate strategies for both instruction and assessment for the study of magnetism across scale.