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K-12 students need to become familiar with engineering because 21st-century careers integrate engineering practices across all science, technology, engineering, and mathematics (STEM) fields. While the Next Generation Science Standards (NGSS) emphasize learning real science and engineering practices, further work is needed to authenticate engineering for K-12 education. The NGSS are presented in a way that merges a single general practice with a core disciplinary idea and cross-cutting concept. Based on this framing and underlying epistemology, NGSS engineering practices are often implemented as overgeneralized, isolated, and largely context-neutral. Yet, in the STEM workplace, practices are rarely done in isolation from one another. Research is needed to better understand the integrated use of NGSS practices in STEM workplaces in order to make these practices more visible and accessible for use in K-12 classrooms. We conducted semi-structured interviews with 22 entry-level employees and managers in STEM-intensive workplaces. Using emergent and a priori coding, we identified how NGSS practices and contextual features are situated and connected in the STEM workplace. Our findings suggest that by adding rich contextual features, practices become more interconnected and reflective of authentic engineering in the STEM workplace. This process will enable educators to interpret K-12 engineering standards in an authentic way that supports deep engagement in learning engineering.

This work aims to understand how effective the typical admissions criteria used in physics are at identifying students who will complete the PhD. Through a multivariate statistical analysis of a sample that includes roughly one in eight students who entered physics PhD programs from 2000-2010, we find that the traditional admissions metrics of undergraduate GPA and the Graduate Records Examination (GRE) Quantitative, Verbal, and Physics Subject Tests do not predict completion in US physics graduate programs with the efficacy often assumed by admissions committees. We find only undergraduate GPA to have a statistically significant association with physics PhD completion across all models studied. In no model did GRE Physics or GRE Verbal predict PhD completion. GRE Quantitative scores had statistically significant relationships with PhD completion in two of four models studied. However, in practice, probability of completing the PhD changed by less than 10 percentage points for students scoring in the 10 ^th vs 90 ^th percentile of US test takers that were physics majors. Noting the significant race, gender, and citizenship gaps in GRE scores, these findings indicate that the heavy reliance on these test scores within typical PhD admissions process is a deterrent to increasing access, diversity, and equity in physics. Misuse of GRE scores selects against already-underrepresented groups and US citizens with tools that fail to meaningfully predict PhD completion. This is a draft; see the journal for the published version. Additionally included in blue text are several responses to queries about this work.

We review and extend existing frameworks on modeling to develop a new framework that describes model-based reasoning in upper-division physics labs. Constructing and using models are core scientific practices that have gained significant attention within K-12 and higher education. Although modeling is a broadly applicable process, within physics education, it has been preferentially applied to the iterative development of broadly applicable principles (e.g., Newton's laws of motion in introductory mechanics). A significant feature of the new framework is that measurement tools (in addition to the physical system being studied) are subjected to the process of modeling. Think-aloud interviews were used to refine the framework and demonstrate its utility by documenting examples of model-based reasoning in the laboratory. When applied to the think-aloud interviews, the framework captures and differentiates students' model-based reasoning and helps identify areas of future research. The interviews showed how students productively applied similar facets of modeling to the physical system and measurement tools: construction, prediction, interpretation of data, identification of model limitations, and revision. Finally, we document students' challenges in explicitly articulating assumptions when constructing models of experimental systems and further challenges in model construction due to students' insufficient prior conceptual understanding. A modeling perspective reframes many of the seemingly arbitrary technical details of measurement tools and apparatus as an opportunity for authentic and engaging scientific sense-making., Comment: 6 figures, 1 Table

Optomechanical devices in which a flexible SiN membrane is placed inside an optical cavity allow for very high finesse and mechanical quality factor in a single device. They also provide fundamentally new functionality: the cavity detuning can be a quadratic function of membrane position. This enables a measurement of "position squared" ($x^2$) and in principle a QND phonon number readout of the membrane. However, the readout achieved using a single transverse cavity mode is not sensitive enough to observe quantum jumps between phonon Fock states. Here we demonstrate an $x^2$-sensitivity that is orders of magnitude stronger using two transverse cavity modes that are nearly degenerate. We derive a first-order perturbation theory to describe the interactions between nearly-degenerate cavity modes and achieve good agreement with our measurements using realistic parameters. We also demonstrate theoretically that the $x^2$-coupling should be easily tunable over a wide range., Comment: 12 pages, 9 figures, ICAP proceeding