Search

Uncertainty is an important and fundamental concept in physics education. Students are often first exposed to uncertainty in introductory labs, expand their knowledge across lab courses, and then are introduced to quantum mechanical uncertainty in upper-division courses. This study is part of a larger project evaluating student thinking about uncertainty across these contexts. In this research, we investigate advanced physics student thinking about uncertainty by asking them conceptual questions about how a hypothetical distribution of measurements would change if "more" or "better" data were collected in four different experimental scenarios. The scenarios include both classical and quantum experiments, as well as experiments that theoretically result in an expected single value or an expected distribution. This investigation is motivated by our goal of finding insights into students' potential point- and setlike thinking about uncertainty and of shining light on the limitations of those binary paradigms.

Prior research has indicated that students in the undergraduate physics lab divide work inequitably with regard to gender. In this work, we further probed women's experiences in lab group work, focusing on women who take on managerial and leadership roles in the lab. We interviewed and surveyed women enrolled in a sophomore-level project-based lab course, drawing on a practice-linked identity framework to characterize their opportunities for engagement and identity development within the course. Although we observed some gender inequities in group work, we also found that taking on a manager role had a positive impact on many women's development of physics lab identity. Our results suggest that instructors should take into account women's individual experiences and preferences for particular roles when structuring equitable group work.

Researchers have pinpointed recognition from others as one of the most important dimensions of students' science and engineering identity. Studies, however, have found gender biases in students' recognition of their peers, with inconsistent patterns across introductory science and engineering courses. Toward finding the source of this variation, we examine whether a gender bias exists in students' nominations of strong peers across three different remote, introductory physics courses with varying student populations (varying demographics, majors, and course levels). We also uniquely evaluate possible racial or ethnic biases and probe the relationship between instructional context (whether lecture or laboratory) and recognition. Some of our results replicate previous findings (such as the association of course grade and small class section enrollment with nominations), while others offer contradictions. Comparing across our three courses and the prior work, results suggest that course level (whether first-year students or beyond-first-year students) might be more associated with a gender bias in peer recognition than other variables. Surprisingly, we also find instances of racial or ethnic biases in favor of students from backgrounds historically underrepresented in science. Finally, we find that the nomination patterns differ when students nominate individuals strong in the lecture material versus the laboratory material. This work serves as an important step in determining which courses and contexts exhibit biases in peer recognition, as well as how students' perceptions of one another form in remote teaching environments.

Engaging in interactions with peers is important for student learning. Many studies have quantified patterns of student interactions in in-person physics courses using social network analysis, finding different network structures between instructional contexts (lecture and laboratory) and styles (active and traditional). Such studies also find inconsistent results as to whether and how student-level variables (e.g., grades and demographics) relate to the formation of interaction networks. In this cross-sectional research study, we investigate these relationships further by examining lecture and lab interaction networks in four different remote physics courses spanning various instructional styles and student populations. We apply statistical methods from social network analysis--exponential random graph models--to measure the relationship between network formation and multiple variables: students' discussion and lab section enrollment, final course grades, gender, and race or ethnicity. Similar to previous studies of in-person courses, we find that remote lecture interaction networks contain large clusters connecting many students, while remote lab interaction networks contain smaller clusters of a few students. Our statistical analysis suggests that these distinct network structures arise from a combination of both instruction-level and student-level variables, including the learning goals of each instructional context, whether assignments are completed in groups or individually, and the distribution of gender and major of students enrolled in a course. We further discuss how these and other variables help to understand the formation of interaction networks in both remote and in-person physics courses.

Physics education research is replete with observations and proposed explanations for gender disparities in physics. In this work, we operationalize a definition for equity as everyone has access to the learning environment and everyone's voice is heard (adapted from previous definitions). We review prior research that observed inequities in physics lab group work and evaluate the degree to which these inequities may arise from student preferences. Regarding access to the learning environment, we find that men and women have similar preferences for experimentation roles, though women generally preferred sharing, rather than dividing or rotating, roles. Regarding everyone's voice being heard, we find that students prefer when no single student takes charge, though many preferred that students take turns leading the group, with no significant differences between men's and women's preferences. We also find no significant differences in men's and women's preferences for the gender composition of their group. We conclude that the observed inequities are not explained by student preference and explore implications for instruction and future research.

Understanding social interactions among students comprises a rich area of physics education research. Here we focus on the social interactions in introductory physics laboratories (labs). Most existing research in such contexts focuses on within-group social dynamics, however, we argue that interactions between different lab groups are just as valuable, especially in nontraditional (reformed) labs where students have more control over the experimental designs. Using video recordings of lab sessions and social network analysis methods, we examined whether and for how long groups interact with each other, comparing across three offerings of an introductory mechanics course. We observed significant variability in the interactions across lab sessions and no clear pattern in how strongly lab groups were connected in the networks between the different courses. More prolonged intergroup interactions, however, occurred in three of the four reformed lab sections, as compared to a traditional lab section and a reformed lab section that took place in the evening. We also developed a group-level social role classification scheme based on groups' interaction patterns, identifying four roles: noninteractors, information seekers, responders, and mutual interactors. We found that groups in the traditional lab section disproportionately acted as noninteractors, indicating that many groups in this lab did not engage in intergroup interactions at all. In contrast, groups in reformed lab sections took on the remaining three roles more frequently. We also found possible relationships between the distributions of the social roles within each type of lab by the groups' gender compositions. All-male groups took on interactive roles more often than all-female and mixed-gender groups in the reformed lab sections, but not in the traditional lab. Results indicate that the amount of time students spend on intergroup interactions may depend on the lab curriculum itself, the time of day of the section, and/or the student population of the section. Still, instructors can encourage collaboration between lab groups through direct prompts, but such prompts need to be repeated throughout the semester.

Instructional labs are fundamental to an undergraduate physics curriculum, but their possible learning goals are vast with limited evidence to support any particular goal. In this study, we evaluate the efficacy of labs with different goals and structures on students' critical thinking skills and views about experimentation, using an extensive database of survey responses from over 20 000 students at over 100 institutions. Here, we show that labs focused on developing experimentation skills improve students' critical thinking skills and experimentation views compared to labs focused on reinforcing lecture concepts. We further demonstrate the positive impacts of skills-based labs over concepts-based labs on these outcomes across students' gender and race or ethnicity. Our analysis also shows that activities to support students' decision making and communication explain over one-half and one-third of the effect of skills-based labs on students' critical thinking skills and experimentation views, respectively, while modeling activities have only a small effect on performance.

As physics laboratory courses (labs) transition from traditional, model-verifying activities to discovery-based investigations, it becomes crucial to understand the role of the instructor in the implementation of various lab types. Prior work has started to address this need by examining either coarse-grained frequencies or fine-grained content of instructor interactions in labs. However, neither of these methods offer both a detailed and time-efficient procedure for measuring such interactions, which is required for comparisons across multiple sessions of several types of labs. Here we describe and present the results of a new approach to quantifying student-instructor interactions in labs by analyzing video recordings and drawing on techniques of social network analysis. Across five sections of three lab course offerings, we find that there is a higher total level of interaction between students and instructors in reformed discovery-based labs than in traditional labs. We find no clear pattern in the durations of student-initiated and instructor-initiated interactions across various instructors and lab types. The results suggest that the amount of interaction between instructors and students during lab is more a product of the instructional design than an individual instructor's implementation of that design. This work is a preliminary step toward understanding the extent to which student-instructor interactions support the improved outcomes observed in discovery-based labs compared with traditional labs.

Instructional physics labs offer students unique opportunities to develop an understanding of experimentation. By transforming labs to be more open ended and experimentation focused, instructors can better support student agency and choice. In this study, we examine students' overall sense of and perceptions about agency in two experimentation-focused labs: one course primarily taken by physics majors and another course primarily taken by engineering majors. We compare the sense of and perceptions about agency between the different courses and between men and women in each course. Between the start and the end of the semester, we found a positive shift in students' sense of agency in the lab activities in both courses, with no difference between men's and women's shifts. Additionally, we found empirical evidence that the majority of the students preferred the final, most open-ended Project lab. Our qualitative analysis revealed that most of the students perceived the opportunities for agency positively, citing "freedom" as their reason for preferring the Project lab. Both women and men in the course for engineering majors showed similar patterns. Fewer women in the physics majors course, however, chose the final project lab as their favorite and less often attributed their preference to freedom. We discuss possible interpretations of these results and implications for instruction.

Omitted variable bias occurs in most statistical models. Whenever a confounding variable that is correlated with both dependent and independent variables is omitted from a statistical model, estimated effects of included variables are likely to be biased due to omitted variables. This issue is particularly problematic in physics education research where many research studies are quasiexperimental or observational in nature due to ethical and logistical limitations. In this paper, we illustrate the mechanisms behind omitted variable bias in explanatory modeling using authentic data and analytical solutions. We demonstrate that omitting confounding variables that are strongly correlated with included variables and have large effects on the dependent variable can significantly bias estimated effects for included variables. We also find that controlling for variables that are uncorrelated with other variables or have no effect on the dependent variable does not appreciably bias estimated effects and may or may not affect the precision of those estimates. These results suggest that removing from explanatory models variables that are not "statistically significant" can have unintended consequences on model and variable interpretations. Our results underscore the importance of carefully considering why or why not to include a variable in a model, informed by both data and theory.

With the adoption of instructional laboratories that require students to make their own decisions, there is a need to better understand students' activities as they make sense of their data and decide how to proceed. In particular, understanding when students do not engage productively with unexpected data may provide insights into how to better support students in more open-ended labs. We examine video and audio data from groups within a lab session where students were expected to find data inconsistent with the predictions of two models. In prior work, we examined the actions of the four groups that productively grapple with this designed problem. Here, we analyze the engagement of the three groups that do not. We conducted three phases of analysis: (1) documenting large scale behaviors and time spent in on-topic discussion; (2) analyzing interactions with the teaching assistant; and (3) identifying students' framing--their expectations for what is taking place--when they were discussing their data. Our phase 1 and 2 analyses show only minor differences between the groups that engaged with the problem and those that did not. Our phase 3 analysis demonstrated that the groups that did not engage with the problem framed the lab activity as about confirming a known result or as a series of hoops to jump through to fulfill assignment requirements. Implications for instruction include supporting teaching assistants to attend to students' framing and agency within laboratory classrooms.

Many instructional physics labs are shifting to teach experimentation skills, rather than to demonstrate or confirm canonical physics phenomena. Our previous work found that many students engage in questionable research practices in attempts to confirm the canonical physics phenomena, even when confirmation is explicitly not the goal of the lab. This exploratory study aimed to answer three research questions: (RQ1) What are students' expectations about the purpose of labs when they enter introductory physics?, (RQ2) How do their prior experiences shape those expectations?, (RQ3) In what ways do those expectations relate to their engagement in questionable research practices? Through open-response surveys, we found that students overwhelmingly expressed confirmatory beliefs about the purpose of labs. Through interviews, we found that students' prior lab experiences were also overwhelmingly confirmatory, despite varying degrees of structure. We then used video of individual groups to explore the ways in which questionable research practices manifest through confirmatory expectations. We confirm previous work that students' confirmatory expectations can lead them to engage in questionable research practices, but find that these behaviors occur despite instructional messaging about an alternative purpose. Our analyses also suggest that engagement in questionable research practices is more frequent than the previous results indicated through analysis of submitted lab notes. These results further illuminate issues with traditional labs, but suggest that the confirmatory goals, perhaps more so than high structure, are problematic.

Scientific expertise is manifested through extensive cycles of making and acting on decisions. To learn the processes and practices of science, therefore, students must have practice with scientific decision making. We argue that this can only happen if students are afforded agency: the opportunity to make decisions to pursue a goal. In this study, we compared two different introductory physics labs through the lens of structuring and supporting student agency. We explore both the role of decision making agency (students are afforded opportunities to make decisions about their lab investigations) and epistemic agency (students are afforded opportunities to generate knowledge). We found that the two labs differed in both the amount and type of structure provided to students: one lab (the intervention condition), with more overall structure, cued student decision making; the other lab (control condition), with less overall structure, made decisions for students. Students in the intervention condition documented, on average, ten times more decisions during their investigations, including more unprompted decisions. In contrast, in labs with less available epistemic agency (i.e., labs where they had to verify or demonstrate canonical models or constants), students in the intervention condition documented fewer decisions than in labs with more available epistemic agency. We associate the improved decision making with students taking up personal agency, based on significant shifts in students' tone as they described their experimental methods (from passive, third-person narratives to active, first-person narratives). Students in the intervention condition also made higher-quality decisions in line with scientific practice. The study speaks to the important nuances between structure and agency in instructional labs and tests the generalizability of previous research on lab instruction to a two-year college population.

Instructional labs are being transformed to better reflect authentic scientific practice, often by removing aspects of pedagogical structure to support student agency and decision making. We explored how these changes impact men's and women's participation in group work associated with labs through clustering methods on the quantified behavior of students. We compared the group roles students take on in two different types of instructional settings: (i) highly structured traditional labs, and (ii) less structured inquiry-based labs. Students working in groups in the inquiry-based (less structured) labs assumed different roles within their groups, however men and women systematically took on different roles and men behaved differently when in single- versus mixed-gender groups. We found no such systematic differences in role division among male and female students in the traditional (highly structured) labs. Students in the inquiry-based labs were not overtly assigned these roles, indicating that the inequitable division of roles was not a result of explicit assignment. Our results highlight the importance of structuring equitable group dynamics in educational settings, as a gendered division of roles can emerge without active intervention. As the culture in physics evolves to remove systematic gender biases in the field, instructors in educational settings must not only remove explicitly biased aspects of curricula but also take active steps to ensure that potentially discriminatory aspects are not inadvertently reinforced.

Physics lab instruction is evolving in response to changing technology, a desire to better prepare students for diverse careers, and renewed focus from physics education researchers. To prepare researchers to evaluate progress in instructional labs in the future, this study set out to understand the current state of instructional physics labs in North America. Using information collected from instructors intending to use two research-based lab assessments, we evaluate the reach, organization, goals, and pedagogies from over 200 unique instructional lab courses at over 100 institutions. We find significant diversity in all aspects evaluated, with some trends in course pedagogy based on course goals and level. Namely, courses that aim to reinforce concepts, develop lab skills, or do both incorporate varied levels of agency and modeling in their instruction, with differences in first year and beyond-first year courses. We hope these analyses will be useful for instructors to situate their own courses in the national landscape and for researchers to evaluate changes in lab instruction in the future.

Introductory physics lab instruction is undergoing a transformation, with increasing emphasis on developing experimentation and critical thinking skills. These changes present a need for standardized assessment instruments to determine the degree to which students develop these skills through instructional labs. In this article, we present the development and validation of the physics lab inventory of critical thinking (PLIC). We define critical thinking as the ability to use data and evidence to decide what to trust and what to do. The PLIC is a 10-question, closed-response assessment that probes student critical thinking skills in the context of physics experimentation. Using interviews and data from 5584 students at 29 institutions, we demonstrate, through qualitative and quantitative means, the validity and reliability of the instrument at measuring student critical thinking skills. This establishes a valuable new assessment instrument for instructional labs.

Instructional labs are widely seen as a unique, albeit expensive, way to teach scientific content. We measured the effectiveness of introductory lab courses at achieving this educational goal across nine different lab courses at three very different institutions. These institutions and courses encompassed a broad range of student populations and instructional styles. The nine courses studied had two key things in common: the labs aimed to reinforce the content presented in lectures, and the labs were optional. By comparing the performance of students who did and did not take the labs (with careful normalization for selection effects), we found universally and precisely no added value to learning course content from taking the labs as measured by course exam performance. This work should motivate institutions and departments to reexamine the goals and conduct of their lab courses, given their resource-intensive nature.We show why these results make sense when looking at the comparative mental processes of students involved in research and instructional labs, and offer alternative goals and instructional approaches that would make lab courses more educationally valuable.

Developing critical thinking skills is a common goal of an undergraduate physics curriculum. How do students make sense of evidence and what do they do with it? In this study, we evaluated students' critical thinking behaviors through their written notebooks in an introductory physics laboratory course. We compared student behaviors in the Structured Quantitative Inquiry Labs (SQILabs) curriculum to a control group and evaluated the fragility of these behaviors through procedural cueing. We found that the SQILabs were generally effective at improving the quality of students' reasoning about data and making decisions from data. These improvements in reasoning and sensemaking were thwarted, however, by a procedural cue.We describe these changes in behavior through the lens of epistemological frames and task orientation, invoked by the instructional moves.

While the positive outcomes of undergraduate research experiences (UREs) have been extensively categorized, the mechanisms for those outcomes are less understood. Through lightly structured focus group interviews, we have extracted the cognitive tasks that students identify as engaging in during their UREs. We also use their many comparative statements about their coursework, especially lab courses, to evaluate their experimental physics-related cognitive tasks in those environments. We find there are a number of cognitive tasks consistently encountered in physics UREs that are present in most experimental research. These are seldom encountered in lab or lecture courses, with some notable exceptions. Having time to reflect and fix or revise, and having a sense of autonomy, were both repeatedly cited as key enablers of the benefits of UREs. We also identify tasks encountered in actual experimental research that are not encountered in UREs. We use these findings to identify opportunities for better integration of the cognitive tasks in UREs and lab courses, as well as discussing the barriers that exist. This work responds to extensive calls for science education to better develop students' scientific skills and practices, as well as calls to expose more students to scientific research.

In a recent report, the American Association of Physics Teachers has developed an updated set of recommendations for curriculum of undergraduate physics labs. This document focuses on six major themes: constructing knowledge, modeling, designing experiments, developing technical and practical laboratory skills, analyzing and visualizing data, and communicating physics. These themes all tie together as a set of practical skills in scientific measurement, analysis, and experimentation. In addition to teaching students "how" to use these skills, it is important for students to know "when" to use them so that they can use them autonomously. This requires, especially in the case of analytical skills, high levels of inquiry behaviors to reflect on data and iterate measurements, which students rarely do in lab experiments. Often, they perform lab experiments in a plug-and-chug frame, procedurally completing each activity with little to no sensemaking. An emphasis on obtaining true theoretical values or agreement on individual measurements also reinforces inauthentic behaviors such as retroactively inflating measurement uncertainties. This paper aims to offer a relatively simple pedagogical framework for engaging students authentically in experimentation and inquiry in physics labs.

Invention activities are Productive Failure activities in which students attempt (and often fail) to invent methods that capture deep properties of a construct before being taught expert solutions. The current study evaluates the effect of scaffolding on the invention processes and outcomes, given that students are not expected to succeed in their inquiry and that all students receive subsequent instruction. While socio-cognitive theories of learning advocate for scaffolding in inquiry activities, reducing students' agency, and possibly their failure rate, may be counter-productive in this context. Two Invention activities related to data analysis concepts were given to 87 undergraduate students in a first-year physics lab course using an interactive learning environment. Guided Invention students outperformed Unguided Invention students on measures of conceptual understanding of the structures of the constructs in an assessment two months after the learning period. There was no effect, however, on measures of procedural knowledge or conceptual understanding of the overall goals of the constructs. In addition, Guided Invention students were more likely to invent multiple methods during the Invention process. These results suggest that the domain-general scaffolding in Invention activities, when followed by instruction, can help students encode deep features of the domain and build on their failures during Productive Failure. These results further suggest not all failures are equally productive, and that some forms of support help students learn form their failed attempts.