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Three-dimensional learning (3DL) is an approach to science instruction that was developed for K-12 science education and that can provide guidance for improving undergraduate physics laboratories. In this paper, we describe efforts to comprehensively integrate 3DL into a sequence of undergraduate introductory physics for life sciences (IPLS) laboratory courses. This paper is tailored for introductory physics faculty interested in advancing their course's learning goals by simultaneously engaging students in experimental practices, scientific reasoning, and conceptual knowledge. We first review how several well-known laboratory curricula are already implicitly aligned with 3DL. We then describe our IPLS course sequence and show how each 3DL dimension—science and engineering practices, disciplinary core ideas, and crosscutting concepts—is integrated throughout the curriculum. To support implementation, we provide samples of our course documentation, a detailed account of our 3DL integration efforts, a guide to training and supporting teaching and learning assistants in a 3DL course, and a sample set of activities to guide students in participating in 3DL instruction in the supplementary material. 

Recent progress achieved in metal-assisted chemical etching (MACE) has enabled the production of high-quality micropillar arrays for various optoelectronic applications. Si micropillars produced by MACE often show a porous Si/SiO_xshell on crystalline pillar cores introduced by local electrochemical reactions. In this paper, we report the distinct optoelectronic characteristics of the porous Si/SiO_xshell correlated to their chemical compositions. Local photoluminescent (PL) images obtained with an immersion oil objective lens in confocal microscopy show a red emission peak (≈ 650 nm) along the perimeter of the pillars that is threefold stronger compared to their center. On the basis of our analysis, we find an unexpected PL increase (≈ 540 nm) at the oil/shell interface. We suggest that both PL enhancements are mainly attributed to the porous structures, a similar behavior observed in previous MACE studies. Surface potential maps simultaneously recorded with topography reveal a significantly high surface potential on the sidewalls of MACE-synthesized pillars (+ 0.5 V), which is restored to the level of planar Si control (− 0.5 V) after removing SiO_xin hydrofluoric acid. These distinct optoelectronic characteristics of the Si/SiO_xshell can be beneficial for various sensor architectures.

 

In efforts to increase scientific literacy and enhance the preparation of learners to pursue careers in science, there are growing opportunities for students and teachers to engage in scientific research experiences, including course-based undergraduate research experiences (CUREs), undergraduate research experiences (UREs), and teacher research experiences (TREs). Prior literature reviews detail a variety of models, benefits, and challenges and call for the continued examination of program elements and associated impacts. This paper reports a comprehensive review of 307 papers published between 2007 and 2017 that include CURE, URE, and TRE programs, with a special focus on research experiences for K–12 teachers. A research-supported conceptual model of science research experiences was used to develop a coding scheme, including participant demographics, theoretical frameworks, methodology, and reported outcomes. We summarize recent reports on program impacts and identify gaps or misalignments between goals and measured outcomes. The field of biology was the predominant scientific disciplinary focus. Findings suggest a lack of studies explicitly targeting 1) participation and outcomes related to learners from underrepresented populations, 2) a theoretical framework that guides program design and analysis, and, for TREs, 3) methods for translation of research experiences into K–12 instructional practices, and 4) measurement of impact on K–12 instructional practices.