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A Construct-Modeling Approach to Develop a Learning Progression of how Students Understand the Structure of Matter
This paper builds on the current literature base about learning progressions in science to address the question, “What is the nature of the learning progression in the content domain of the structure of matter?” We introduce a learning progression in response to that question and illustrate a methodology, the Construct Modeling (Wilson, 2005) approach, for investigating the progression through a developmentally based iterative process. This study puts forth a progression of how students understand the structure of matter by empirically inter-relating constructs of different levels of sophistication using a sample of 1,087 middle grade students from a large diverse public school district in the western part of the United States. The study also shows that student thinking can be more complex than hypothesized as in the case of our discovery of a substructure of understanding in a single construct within the larger progression. Data were analyzed using a multidimensional Rasch model. Implications for teaching and learning are discussed—we suggest that the teacher’s choice of instructional approach needs to be fashioned in terms of a model, grounded in evidence, of the paths through which learning might best proceed, working toward the desired targets by a pedagogy which also cultivates students’ development as effective learners. This research sheds light on the need for assessment methods to be used as guides for formative work and as tools to ensure the learning goals have been achieved at the end of the learning period. The development and investigation of a learning progression of how students understand the structure of matter using the Construct Modeling approach makes an important contribution to the research on learning progressions and serves as a guide to the planning and implementation in the teaching of this topic. # 2017 Wiley Periodicals, Inc. J Res Sci Teach 54: 1024–1048, 201
Teaching and understanding of quantum interpretations in modern physics courses
Just as expert physicists vary in their personal stances on interpretation in
quantum mechanics, instructors vary on whether and how to teach interpretations
of quantum phenomena in introductory modern physics courses. In this paper, we
document variations in instructional approaches with respect to interpretation
in two similar modern physics courses recently taught at the University of
Colorado, and examine associated impacts on student perspectives regarding
quantum physics. We find students are more likely to prefer realist
interpretations of quantum-mechanical systems when instructors are less
explicit in addressing student ontologies. We also observe contextual
variations in student beliefs about quantum systems, indicating that
instructors who choose to address questions of ontology in quantum mechanics
should do so explicitly across a range of topics.Comment: 18 pages, references, plus 2 pages supplemental materials. 8 figures.
PACS: 01.40.Fk, 03.65.-
Interpretive Themes in Quantum Physics: Curriculum Development and Outcomes
A common learning goal for modern physics instructors is for students to
recognize a difference between the experimental uncertainty of classical
physics and the fundamental uncertainty of quantum mechanics. Our prior work
has shown that student perspectives on the physical interpretation of quantum
mechanics can be characterized, and are differentially influenced by the myriad
ways instructors approach interpretive themes in their introductory courses. We
report how a transformed modern physics curriculum (recently implemented at the
University of Colorado) has positively impacted student perspectives on quantum
physics, by making questions of classical and quantum reality a central theme
of the course, but also by making the beliefs of students (and not just those
of scientists) an explicit topic of discussion.Comment: Supporting materials available at
http://tinyurl.com/baily-dissertatio
Evolution of Network Architecture in a Granular Material Under Compression
As a granular material is compressed, the particles and forces within the system arrange to form complex and heterogeneous collective structures. Force chains are a prime example of such structures, and are thought to constrain bulk properties such as mechanical stability and acoustic transmission. However, capturing and characterizing the evolving nature of the intrinsic inhomogeneity and mesoscale architecture of granular systems can be challenging. A growing body of work has shown that graph theoretic approaches may provide a useful foundation for tackling these problems. Here, we extend the current approaches by utilizing multilayer networks as a framework for directly quantifying the progression of mesoscale architecture in a compressed granular system. We examine a quasi-two-dimensional aggregate of photoelastic disks, subject to biaxial compressions through a series of small, quasistatic steps. Treating particles as network nodes and interparticle forces as network edges, we construct a multilayer network for the system by linking together the series of static force networks that exist at each strain step. We then extract the inherent mesoscale structure from the system by using a generalization of community detection methods to multilayer networks, and we define quantitative measures to characterize the changes in this structure throughout the compression process. We separately consider the network of normal and tangential forces, and find that they display a different progression throughout compression. To test the sensitivity of the network model to particle properties, we examine whether the method can distinguish a subsystem of low-friction particles within a bath of higher-friction particles. We find that this can be achieved by considering the network of tangential forces, and that the community structure is better able to separate the subsystem than a purely local measure of interparticle forces alone. The results discussed throughout this study suggest that these network science techniques may provide a direct way to compare and classify data from systems under different external conditions or with different physical makeup
Bridging Physics and Biology Teaching through Modeling
As the frontiers of biology become increasingly interdisciplinary, the
physics education community has engaged in ongoing efforts to make physics
classes more relevant to life sciences majors. These efforts are complicated by
the many apparent differences between these fields, including the types of
systems that each studies, the behavior of those systems, the kinds of
measurements that each makes, and the role of mathematics in each field.
Nonetheless, physics and biology are both sciences that rely on observations
and measurements to construct models of the natural world. In the present
theoretical article, we propose that efforts to bridge the teaching of these
two disciplines must emphasize shared scientific practices, particularly
scientific modeling. We define modeling using language common to both
disciplines and highlight how an understanding of the modeling process can help
reconcile apparent differences between the teaching of physics and biology. We
elaborate how models can be used for explanatory, predictive, and functional
purposes and present common models from each discipline demonstrating key
modeling principles. By framing interdisciplinary teaching in the context of
modeling, we aim to bridge physics and biology teaching and to equip students
with modeling competencies applicable across any scientific discipline.Comment: 10 pages, 2 figures, 3 table
Teaching Quantum Interpretations: Revisiting the goals and practices of introductory quantum physics courses
Most introductory quantum physics instructors would agree that transitioning
students from classical to quantum thinking is an important learning goal, but
may disagree on whether or how this can be accomplished. Although (and perhaps
because) physicists have long debated the physical interpretation of quantum
theory, many instructors choose to avoid emphasizing interpretive themes; or
they discuss the views of scientists in their classrooms, but do not adequately
attend to student interpretations. In this synthesis and extension of prior
work, we demonstrate: (1) instructors vary in their approaches to teaching
interpretive themes; (2) different instructional approaches have differential
impacts on student thinking; and (3) when student interpretations go
unattended, they often develop their own (sometimes scientifically undesirable)
views. We introduce here a new modern physics curriculum that explicitly
attends to student interpretations, and provide evidence-based arguments that
doing so helps them to develop more consistent interpretations of quantum
phenomena, more sophisticated views of uncertainty, and greater interest in
quantum physics.Comment: 14 pages, 11 figures; submitted to PRST-PER: Focused Collection on
Upper-Division PER. arXiv admin note: text overlap with arXiv:1409.849
Making connections in science: engaging with ICT to enhance curriculum understanding
The “Teaching Teachers for the Future” (TTF) project (DEEWR, 2012) provided the La Trobe University School of Education with the opportunity to rethink the integration of Information and Communication Technology in the science curriculum subjects offered in their teacher education programs.
The La Trobe University iteration of the Teaching Teachers for the Future (TTF) project focused initially on subject in the second semester, third year of the Bachelor of Education course called the Multi-Disciplinary Science & Technology Integrated Experience (MSTIE). Two pairs of pre-service teachers were placed in the school where the TTF ICT Pedagogy Officer (ICTPO) worked as an ICT specialist. The two teams worked with classroom teachers and the ICTPO to cooperatively plan, teach and evaluate a science curriculum project enhanced by strong ICT integration. The experience was a catalyst for significant educational insight, for the students involved, but also for other pre-service teachers and teachers from the school and university.
In the second cycle of the project the ICTPO worked with academics from the university to draw on findings from the first cycle in order to design and implement integrated ICT initiatives in a first semester, second year Science curriculum subject. This structure means that students who will take MSTIE in their third year will have a strong foundation of Science ICT integration on which to base their MSTIE preparation and implementation.
 
Quantum-optical influences in optoelectronics - an introduction
This focused review discusses the increasing importance of quantum optics in the physics and engineering of optoelectronic components. Two influences relating to cavity quantum electrodynamics are presented. One involves the development of low threshold lasers, when the channeling of spontaneous emission into the lasing mode becomes so efficient that the concept of lasing needs revisiting. The second involves the quieting of photon statistics to produce single-photon sources for applications such as quantum information processing. An experimental platform, consisting of quantum-dot gain media inside micro- and nanocavities, is used to illustrate these influences of the quantum mechanical aspect of radiation. An overview is also given on cavity quantum electrodynamics models that may be applied to analyze experiments or design devices.EC/FP7/615613/EU/External Quantum Control of Photonic Semiconductor Nanostructures/EXQUISIT
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