Introductory physics is taught to several hundred thousand university students every year. It is seen as especially difficult by many and the failure rate is often high. A relevant question is whether one can increase the success rate among the weaker students? Retrieval practice is an established learning strategy with large benefits. However, as pointed out last year in this journal, hardly any systematic research has been done on retrieval practice in physics. Here we present a novel tool for retrieval practice in physics called the hierarchical principle structure for mechanics (HPSM). HPSM hierarchically organizes the essential principles, equations, and definitions for translational, rotational, and fluid mechanics, to emphasize meaningful connections. We investigated HPSM in a two-phase study. First, we present a randomized controlled experiment showing that 70 min of retrieval practice of HPSM had a very large effect on a declarative factual test compared to 70 min of problem study, $d=1.42$. In the second phase, which was carried out the following year, we implemented distributed retrieval practice of HPSM in the first 15 min of 16 lectures. Although difficult to disentangle the effect from the lectures it was embedded in, distributed retrieval practice of HPSM seems to promote factual knowledge ($r=0.44$) and better exam results for the weaker students (significant main and interaction effects).

The topic of women in graduate education has been central to many calls for action in increasing diversity and inclusion in science, technology, engineering, and mathematics. The field of physics has been particularly resistant to change in the significant overrepresentation of men, while also being similar to the field of astronomy which has a higher overall representation of women than many other physical sciences. Little research has been done in the field of astronomy to better understand how women can be supported in other physical sciences. This paper presents an analysis of five women students in a U.S. astronomy graduate program. The results indicate the women in this study relied on student-student collaboration to succeed through their coursework and exams, while faculty and post-doctorate support were critical for their research perseverance. Furthermore, the career goals of these successful students indicate the importance of considering multiple life goals in determining a student’s pathway, and potentially suggests that the way faculty careers progress needs to be reconsidered if the field wants more diverse faculty and role models.

Self-efficacy is an aspect of students’ motivation that has been shown to play a critical role in students’ engagement, participation, and retention in academic careers in science, technology, engineering, and mathematics (STEM). Since women are underrepresented in STEM domains such as physics, we studied female and male students’ self-efficacy and its relation to learning outcomes in physics that can be useful for creating equitable and inclusive learning environments. In a longitudinal study, we surveyed approximately 1400 students in calculus-based physics 2 courses to investigate students’ motivational beliefs in physics using a validated survey. We examined female and male students’ self-efficacy scores and the extent to which self-efficacy related to learning outcomes (students’ grades and conceptual post-test scores), especially the significant gender difference in conceptual post-test scores. To reveal the unique contribution of self-efficacy on outcomes, we controlled for several other variables including Physics 1 grades, SAT math scores, and conceptual pretest scores in physics. We found that the gender differences in conceptual post-test performance were mediated by the model variables. In particular, initial self-efficacy differences showed a direct effect on outcomes even when controlling for students’ prior physics knowledge and skill differences, and self-efficacy also had the strongest total gender effect on conceptual learning. Given these findings, future work should focus on better understanding the drivers of these self-efficacy differences including the role that societal stereotypes and biases play in these in order to mitigate these differences.

Many science, technology, engineering, and math degrees require passing an introductory physics course. Physics courses often have high failure rates that disproportionately harm students who are historically and continually marginalized by racism, sexism, and classism. We examined the associations between learning assistant (LA) supported courses and equity in nonpassing grades [i.e., drop, fail, or withdrawal (DFW)] in introductory physics courses. The data used in the study came from 2312 students in 41 sections of introductory physics courses at a regional Hispanic serving institution. We developed hierarchical generalized linear models of student DFW rates that accounted for gender, race, first-generation status, and LA-supported instruction. We used a quantitative critical race theory (QuantCrit) perspective focused on the role of hegemonic power structures in perpetuating inequitable student outcomes. Our QuantCrit perspective informed our research questions, methods, and interpretations of findings. The models associated LAs with overall decreases in DFW rates and larger decreases in DFW rates for Black, Indigenous, and people of color than their White peers. While the inequities in DFW rates were lower in LA-supported courses, they were still present.

Systematic research on physics teacher education (PTE) programs in the United States is rare, owing both to the great variety of practices and structures enacted by U.S. PTE programs and to the lack of measurement tools available to measure what successful PTE programs do. To help meet the need for a specific, objective, and reliable guide for research on PTE programs, the Physics Teacher Education Coalition developed the Physics Teacher Education Program Analysis (PTEPA) rubric, which characterizes the practices and structures observed at “thriving” PTE programs (defined as programs in the U.S. that frequently graduate five or more physics teachers per year). Initial research based on the PTEPA rubric suggests that thriving programs are strong in multiple areas (especially institutional commitment, leadership, and collaboration among partners in education and physics), and that several areas of strength align with those indicated by the existing PTE literature. However, thriving programs are not necessarily strong in all areas, instead reflecting local conditions at the institutional and state level. Such findings illustrate the opportunity for measurement and hypothesis testing about the most important features that PTE programs should have.

Given the insufficient number of well-qualified future physics teachers in the U.S., physics programs often seek guidance for how to address this national need. Measurement tools can provide such guidance, by both defining excellence in physics teacher education (PTE) and providing a means to measure progress towards excellence. This paper describes the development of such a measurement tool—the Physics Teacher Education Program Analysis rubric. The rubric was developed by identifying common features and practices at 8 “thriving” PTE programs, defined as large U.S. programs consistently graduating 5 or more future physics teachers in a year. The rubric consists of 89 items, each with 3 levels of achievement (developing, benchmark, exemplary), plus a not present level, which are organized into 6 standards. The rubric has demonstrated a variety of forms of validity, including a strong theoretical basis, empirical validation through program visits, and expert review. The rubric and its associated supporting materials are intended to help program leaders in using a process of continuous improvement and assessment to strengthen existing PTE programs or to establish new pathways for student licensure. The rubric also provides substantive opportunities for research, through further validation and development of the rubric, and by using rubric results to learn more about effective practices in physics teacher education.

In recent years, there has been an increased interest in conceptual blending in physics and mathematics education research as a theoretical framework to study student reasoning. In this paper, we adapt the conceptual blending framework to construct a blending diagram that not only captures the product but also the process of student reasoning when they interpret a mathematical description of a physical system. We describe how to construct a dynamic blending diagram (DBD) and illustrate this using two cases from an interview study. In the interview, we asked pairs of undergraduate physics and mathematics students about the physical meaning of boundary conditions for the heat equation. The selected examples show different aspects of the DBD as an analysis method. We show that by using a DBD, we can judge the degree to which students integrate their understandings of mathematics and physics. The DBD also enables the reader to follow the line of reasoning of the students. Moreover, a DBD can be used to diagnose difficulties in student reasoning.

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.

The concepts of the Coriolis and the centrifugal force are essential in various scientific fields and they are standard components of introductory physics lectures. In this paper, we explore how students understand and apply concepts of rotating frames of reference in the context of an example lecture demonstration experiment. We found in a predict-observe-explain setting that after predicting the outcome prior to the demonstration, only one out of five physics students correctly reported the observation of the trajectory of a sphere rolling over a rotating disc. Despite this low score, a detailed analysis of distractors revealed a significant improvement in the distractor choices during the observation of the experiment. In this context, we identified three main preconceptions and learning difficulties: The centrifugal force seems to be only required to describe the trajectory if the object is coupled to the rotating system, the inertial forces cause a reaction of an object on which they act, and students systematically mix up the trajectories in the stationary and the rotating frame of reference. Furthermore, we captured students’ eye movements during the predict task and found that physics students with low confidence ratings focused longer on relevant task areas than confident students despite having a comparable score. Consequently, this metric is a helpful tool for the identification of preconceptions using eye tracking. Overall, the results help us to understand the complexity of concept learning from demonstration experiments and provide important implications for instructional design of introductions to rotating frames of reference.

In this article, we discuss the development and the administration of a multiple-choice test, which we named Test of Calculus and Vectors in Mathematics and Physics (TCV-MP), aimed at comparing students’ ability to answer questions on derivatives, integrals, and vectors in a purely mathematical context and in the context of physics. The comparison between the two contexts was achieved by using parallel (isomorphic) questions in mathematics and physics. The final version of the test contains 34 items (17 in a purely mathematical context and 17 in the context of physics) involving different representations (graphs, words, numbers, and formal expressions) of the concepts covered by the test. The test was administered in Spring 2018 to 1252 first-year students enrolled in 23 different degree programs of the School of Science and the School of Engineering of the University of Padua. We assessed the validity, reliability, and discriminatory power of the test both as a whole and at the single-item level, obtaining values within the desired ranges. The analysis of students’ answers to individual items and the comparison between parallel mathematics and physics items provides insights into the factors that affect students’ ability to use derivatives, integrals, and vectors in the context of introductory physics. We believe that the instrument we have developed can be useful not only for research purposes, but also for instructors and for students.

The goal of this research is to provide a rich set of connections between two fields: (i) Nanoscale science and technology (NST) and (ii) topics from a common middle school physics curriculum. NST is emerging as one of the most promising new fields of the 21st century, which is one of the many arguments for including NST topics in secondary science education. A specially designed guided discourse with NST scientists was used to produce a map of connections between the two fields. During the discourse, the scientists were presented with two sets of concepts using a visual board and were asked to find connections between them. All suggested connections and the corresponding context offered by the scientists were arranged and presented as a rich set of connections. For example, (i) the NST concept of characterization methods is connected to mechanical forces and can be explained using the example of an atomic force microscope; (ii) the NST concept of size-dependent properties was connected to 7th grade inquiry skills by explaining the size dependence of accuracy, errors, and defects. This set of connections was validated by an experienced middle school science teacher in an open discussion regarding teachers adopting and implementing the resulting insertion points for the curriculum. This resulting set of connections can be used to enrich the curriculum within the NST field. It also provides a perspective on scientists’ views regarding insertion of contemporary NST topics into physics middle school education.

We report the findings of an empirical study that investigated whether the source of data—firsthand or secondhand data gained from lab work experiments—has an influence on students’ learning outcomes. Results indicate that students’ choice of a correct or incorrect hypothesis for a pendulum lab experiment on the influence of the mass of the bob on the time of oscillation does not depend on who the author of the data at hand is: the student themself, a peer, or a teacher. Further, students judge the importance of the data’s author as relatively unimportant no matter what data source they have at hand. Thus, it seems fairly unimportant whether students use firsthand or secondhand data when the teaching focus is set on choosing a correct hypothesis in the light of empirical data, as long as students get enough information on how the data were generated and how they are analyzed and interpreted. This result is especially relevant for practitioners, as it shows that it is possible to use secondhand data for the purpose of evaluation and interpretation without significant distortions of epistemic learning processes.

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.

Recently, Nissen et al. argued in this journal for the use of Cohen’s $d$, in place of the more commonly used normalized gain, in the analysis of preinstruction and postinstruction scores on concept inventories used to measure the effectiveness of instruction. Their reason for advocating such a change is that they say normalized gains are “prescore biased.” We provide five examples, including one cited by Nissen, that show no prescore bias when data are carefully analyzed, demonstrating that the problem with their analysis is omitted variable bias. We show that Cohen’s $d$ is less informative than normalized gain when used as a single parameter measure of teaching effectiveness, even though, as Nissen points out, $d$ is more widely used in other fields. We believe that physics education researchers should continue to use normalized gain to assess educational effectiveness of pedagogy. However, because different student populations can have significantly different responses to the same pedagogy, in any interpretation of normalized gain, it is important to consider a measure of the abilities of the students. In analyzing normalized gains for the Force Concept Inventory (FCI), average scores on either Lawson’s Test of Scientific Reasoning Ability or the SAT should be considered, because these scores are strongly correlated with normalized gain, indicating student abilities may have a greater impact on the gains achieved in a class than the specific pedagogy used.

Research-based assessment instruments (RBAIs) are ubiquitous throughout both physics instruction and physics education research. The vast majority of analyses involving student responses to RBAI questions have focused on whether or not a student selects correct answers and using correctness to measure growth. This approach often undervalues the rich information that may be obtained by examining students’ particular choices of incorrect answers. In the present study, we aim to reveal some of this valuable information by quantitatively determining the relative correctness of various incorrect responses. To accomplish this, we propose an assumption that allows us to define relative correctness: students who have a high understanding of Newtonian physics are likely to answer more questions correctly and also more likely to choose better incorrect responses than students who have a low understanding. Analyses using item response theory align with this assumption, and Bock’s nominal response model allows us to uniquely rank each incorrect response. We present results from over 7000 students’ responses to the Force and Motion Conceptual Evaluation.

Nearly every introductory physics or chemistry course includes live lecture demonstrations, which can range from simple illustrations of a pendulum to elaborate productions with specialized apparatus and highly trained demonstrators. Students and instructors often consider “demos” to be among the highlights of these classes. Yet, in some situations demos may be cumbersome, inaccessible, or otherwise unavailable, and online video demos could offer a convenient alternative. We compared the effectiveness of live demonstrations with online videos under controlled conditions in the first semester of an introductory physics (mechanics) course. Students were randomly assigned to view either a live or video version of two demos. The same instructor presented both versions of the demo using an identical script, keeping the same time on task across both conditions, but with small differences in presentation appropriate to the medium. Compared with the students who saw the live demos, the students who watched the online videos learned more, and their self-reported enjoyment was just as high. We discuss reasons why videos helped students to learn more, including that they are more likely to make correct observations from the video. These results suggest that videos could provide students with an equally effective learning experience when live demos are unavailable. Indeed, even when live demonstrations are available, it may be beneficial to supplement them with online presentations.

As targeted, single-conception curriculum research becomes more prevalent in physics education research (PER), the need for a more sophisticated statistical understanding of the conceptual surveys used becomes apparent. Previously, the factor structure of the Force Concept Inventory (FCI) was examined using exploratory factor analysis (EFA) and exploratory multitrait item response theory (EMIRT). The resulting exploratory driven factor model and two expert-proposed models were tested using confirmatory factor analysis (CFA) and were found to be adequate representations of the FCI’s factor structure for postinstruction student responses. This study compliments the literature by using confirmatory multitrait item response theory (CMIRT) on matched preinstruction to postinstruction student responses ($N=19745$). It was found that the proposed models did not fit the data within a CMIRT framework. To determine why these models did not fit the data, an EMIRT was performed to find suggested modifications to the proposed models. This resulted in a bi-factor structure for the FCI. After calculating the student ability scores for each trait in the modified factor models, only two traits in each of the models were found to exhibit student gains independent of the general, “Newtonian-ness” trait. These traits measure students’ understanding of Newton’s third law and their ability to identify forces acting on objects.

The Force Concept Inventory (FCI) can serve as a summative assessment of students’ conceptual knowledge at the end of introductory physics, but previous work has suggested that the knowledge measured by this instrument is not a unitary construct. In this article, we consider the idea that FCI performance may reflect a number of student attributes including relational knowledge structures of physics concepts, expertlike attitudes, and problem-solving skills. Using a large calculus-based introductory physics course, we show that knowledge of conceptual relationships (i.e., knowledge structures), attitudinal measures, and problem-solving ability are all measures that uniquely contribute to a postinstruction FCI score. While these associations do not reveal the nature of their relation to the FCI (it could be that good students perform well on all these measures), they do provide evidence that improving any one of these aspects may improve a student’s overall FCI score.

Students must actively engage in problem solving to effectively learn in introductory physics courses. However, students often get stuck and are not able to make progress when solving problems outside of their current ability, particularly when one-on-one tutoring and instructor office hours are a limited resource. One effective technique consists of providing students with worked examples during the problem-solving process. While the benefits of worked examples are well established, less is known about how the format of the worked example affects student learning, or the effect of solution videos on student metacognition. This study presents three experiments investigating how the format of animated worked examples affects student learning and metacognition. The results indicate that students learn equally well from different styles of solution videos that follow multimedia learning principles. In addition, attempting to solve problems before viewing the solution videos facilitates learning for problems just outside a student’s current ability, but not for more difficult problems. Further, attempting to solve very difficult problems before viewing animated solution videos can potentially lead to overconfidence, where students believe that they learned more from the solutions than they have actually learned.

We elaborate on a new approach of assessing content-based epistemic clarity of college physics students in terms of their ability to discriminate between different epistemic warrants for propositions in a chained argument in physics. A threefold classification (nominal, physical, and mathematical) of warrants is used, with each class split into a number of distinct epistemic categories. The assessment tool consists of a questionnaire, illustrated here for a standard undergraduate physics derivation, in which the student chooses the appropriate epistemic category (from an appended list) for each proposition in the given derivation. The tool includes a brief supplementary orientation note for clarifying the meaning of different categories. It is tested for reliability and internal consistency. Correlation of content knowledge, ascertained independently, with epistemic clarity is investigated. Surveys on large and diverse samples of physics undergraduates carried out with or without the orientation note reveal a variety of epistemic errors, some common among all groups of students, and some that are good discriminators. The epistemic measure obtained from such a tool is, however, limited in scope by its narrow definition. The construct validity of the tool and the pedagogic relevance of the work are discussed.