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The COVID-19 pandemic upended the U.S. education system in ways that dramatically affected the jobs of K–12 employees. However, there remains considerable uncertainty about the nature and degree of staffing challenges during the pandemic. We draw on data from the Bureau of Labor Statistics (BLS) and State Education Agencies (SEA) to describe patterns in K–12 education employment and to highlight the limitations of available data. Data from the BLS suggest overall employment in the K–12 labor market declined by 9 percent at the onset of the pandemic and remained well below pre-pandemic levels more than two years later. SEA data suggest that teachers did not leave the profession en masse as many predicted, with turnover decreasing in the summer of 2020 and then increasing modestly in 2021 back to pre-pandemic levels. We explore possible explanations for these patterns including weak hiring through the summer of 2020 and high attrition among K–12 instructional support and noninstructional staff. State vacancy data also suggest that schools faced substantial challenges filling open positions during the 2021–22 academic year. Our analyses illustrate the imperative to build nationally representative, detailed, and timely data systems on the K–12 education labor market to better inform policy.

We study the adoption and implementation of a new mobile communication application (app) among a sample of 132 New York City public schools. The app provides a platform for sharing general announcements and news, as well as engaging in personalized two-way communication with individual parents. We provide participating schools with free access to the app and randomize schools to receive intensive support (training, guidance, monitoring, and encouragement) for maximizing the efficacy of the app. Although user supports led to higher levels of communication within the app in the treatment year, overall usage remained low and declined in the following year when treatment schools no longer received intensive supports. We find few subsequent effects on perceptions of communication quality or student outcomes. We leverage rich internal user data to explore how take-up and usage patterns varied across staff and school characteristics. These analyses help to identify early adopters and reluctant users, revealing both opportunities and obstacles to engaging parents through new communication technology.

Economic downturns can cause major funding shortfalls for U.S. public schools, often forcing districts to make difficult budget cuts, including teacher layoffs. In this brief, we synthesize the empirical literature on the widespread teacher layoffs caused by the Great Recession. Studies find that teacher layoffs harmed student achievement and were inequitably distributed across schools, teachers, and students. Research suggests that specific elements of the layoff process can exacerbate these negative effects. Seniority-based policies disproportionately concentrate layoffs among teachers of color, who are more likely to be early career teachers. These “last-in first-out” policies also disproportionately affect disadvantaged students because these students are more likely to be taught by early career teachers. The common practice of widely distributing pink slips warning about a potential job loss also appears to increase teacher churn and negatively impact teacher performance. Drawing on this evidence, we outline a set of policy recommendations to minimize the need for teacher layoffs during economic downturns and ensure that the burden of any unavoidable job cuts does not continue to be borne by students of color and students from low-income backgrounds.

COVID-19 shuttered schools across the United States, upending traditional approaches to education. We examine teachers’ experiences during emergency remote teaching in the spring of 2020 using resp...

A core motivation for the widespread teacher evaluation reforms of the past decade was the belief that these new systems would promote teacher development through high-quality feedback. We examine this theory by studying teachers’ perceptions of evaluation feedback in Boston Public Schools and evaluating the district's efforts to improve feedback through an administrator training program. Teachers generally reported that evaluators were trustworthy, fair, and accurate but that they struggled to provide high-quality feedback. We find little evidence that the training program improved perceived feedback quality, classroom instruction, teacher self-efficacy, or student achievement. Our results illustrate the challenges of using evaluation systems as engines for professional growth when administrators lack the time and skill necessary to provide frequent, high-quality feedback.

This article describes and evaluates a web-based coaching program designed to support teachers in implementing Common Core–aligned math instruction. Web-based coaching programs can be operated at relatively lower costs, are scalable, and make it more feasible to pair teachers with coaches who have expertise in their content area and grade level. Results from our randomized field trial document sizable and sustained effects on both teachers’ ability to analyze instruction and on their instructional practice, as measured by the Mathematical Quality of Instruction instrument and student surveys. However, these improvements in instruction did not result in corresponding increases in math test scores as measured by state standardized tests or interim assessments. We discuss several possible explanations for this pattern of results.

In-person tutoring programs can have large impacts on K-12 student achievement, but high program costs and limited local supply of tutors have hampered scale-up. Online tutoring provided by volunteers can potentially reach more students in need. We implemented a randomized pilot program of online tutoring that paired college volunteers with middle school students. We estimate consistently positive but statistically insignificant effects on student achievement, 0.07 standard deviations for math and 0.04 standard deviations for reading. While our estimated effects are smaller than those for many higher-dosage in-person programs, they are from a significantly lower-cost program delivered within the challenging context of the COVID-19 pandemic.

Glycans are ubiquitous and play important biological roles, yet chemical methods for probing their structure and function within cells remain limited. Strategies for studying other biomacromolecules, such as proteins, often exploit chemoselective reactions for covalent modification, capture, or imaging. Unlike amino acids that constitute proteins, glycan building blocks lack distinguishing reactivity because they are composed primarily of polyol isomers. Moreover, encoding glycan variants through genetic manipulation is complex. Therefore, we formulated a new, generalizable strategy for chemoselective glycan modification that directly takes advantage of cellular glycosyltransferases. Many of these enzymes are selective for the products they generate yet promiscuous in their donor preferences. Thus, we designed reagents with bioorthogonal handles that function as glycosyltransferase substrate surrogates. We validated the feasibility of this approach by synthesizing and testing probes of d-arabinofuranose (d-Araf), a monosaccharide found in bacteria and an essential component of the cell wall that protects mycobacteria, including Mycobacterium tuberculosis. The result is the first probe capable of selectively labeling arabinofuranose-containing glycans. Our studies serve as a platform for developing new chemoselective labeling agents for other privileged monosaccharides. This probe revealed an asymmetric distribution of d-Araf residues during mycobacterial cell growth and could be used to detect mycobacteria in THP1-derived macrophages.

We examine the dynamic nature of teacher skill development using panel data on principals’ subjective performance ratings of teachers. Past research on teacher productivity improvement has focused primarily on one important but narrow measure of performance: teachers’ value‐added to student achievement on standardized tests. Unlike value‐added, subjective performance ratings provide detailed information about specific skill dimensions and are available for teachers in non‐tested grades and subjects. Using a within‐teacher returns‐to‐experience framework, we find, on average, large and rapid improvements in teachers’ instructional practices throughout their first 10 years on the job as well as substantial differences in improvement rates across individual teachers. We also document that subjective performance ratings contain important information about teacher effectiveness. In the district we study, principals appear to differentiate teacher performance throughout the full distribution instead of just in the tails. Furthermore, prior performance ratings and gains in these ratings provide additional information about teachers’ ability to improve test scores that is not captured by prior value‐added scores. Taken together, our study provides new insights on teacher performance improvement and variation in teacher development across instructional skills and individual teachers.

Glycans are ubiquitous and play important biological roles, yet chemical methods for probing their structure and function within cells remain limited. Strategies for studying other biomacromolecules, such as proteins, often exploit chemoselective reactions for covalent modification, capture, or imaging. Unlike amino acids that constitute proteins, glycan building blocks lack distinguishing reactivity because they are composed primarily of polyol isomers. Moreover, encoding glycan variants through genetic manipulation is complex. Therefore, we formulated a new, generalizable strategy for chemoselective glycan modification that directly takes advantage of cellular glycosyltransferases. Many of these enzymes are selective for the products they generate yet promiscuous in their donor preferences. Thus, we designed reagents with bioorthogonal handles that function as glycosyltransferase substrate surrogates. We validated the feasibility of this approach by synthesizing and testing probes of D-arabinofuranose (D-Araf), a monosaccharide found in bacteria and an essential component of the cell wall that protects mycobacteria, including Mycobacterium tuberculosis. The result is the first probe capable of selectively labeling arabinofuranose-containing glycans. Our studies serve as a platform for developing new chemoselective labeling agents for other privileged monosaccharides. This probe revealed an asymmetric distribution of D-Araf residues during mycobacterial cell growth and could be used to detect mycobacteria in THP1-derived macrophages.

The purpose of this paper is to outline what we believe to be promising a strategy for developing a scalable behavioral intervention to encourage teachers to adopt teaching practices that support a growth-mindset classroom culture. We first briefly review the most widely-implemented current policies and programs aimed at influencing teachers' instructional practices and consider, based on the available research, how effective those approaches are likely to be for encouraging growth mindset-supportive teaching practices. We then lay out what we believe to be the most important psychological forces currently at play, either facilitating or hindering teachers’ adoption of such practices. On the basis of this analysis of existing psychological forces, and drawing ideas from the research literature in four complementary disciplines, we propose an “intervention toolkit”—candidate intervention ideas that we suggest should be considered for inclusion as components of a larger intervention. Throughout, we identify additional issues for consideration in designing the intervention and important questions for future research.

Teacher coaching has emerged as a promising alternative to traditional models of professional development. We review the empirical literature on teacher coaching and conduct meta-analyses to estimate the mean effect of coaching programs on teachers’ instructional practice and students’ academic achievement. Combining results across 60 studies that employ causal research designs, we find pooled effect sizes of 0.49 standard deviations (SD) on instruction and 0.18 SD on achievement. Much of this evidence comes from literacy coaching programs for prekindergarten and elementary school teachers in the United States. Although these findings affirm the potential of coaching as a development tool, further analyses illustrate the challenges of taking coaching programs to scale while maintaining effectiveness. Average effects from effectiveness trials of larger programs are only a fraction of the effects found in efficacy trials of smaller programs. We conclude by discussing ways to address scale-up implementation challenges and providing guidance for future causal studies.

The vast differences in summer learning activities among children present a substantial challenge to providing equal educational opportunity in the United States. Most initiatives aimed at reversing summer learning loss focus on school- or center-based programs. This study explores the potential of enabling parents to provide literacy development opportunities at home as a low-cost alternative. We conduct a randomized field trial of a summer text-messaging pilot program for parents focused on promoting literacy skills among first through fourth graders. We find positive effects on reading comprehension among third and fourth graders, with effect sizes of .21 to .29 standard deviations, but no effects for first and second graders. Texts also increased attendance at parent-teacher conferences but not at other school-related activities. Evidence to inform future efforts to reverse summer learning loss is provided by parents’ responses to a follow-up survey.

I exploit the random assignment of class rosters in the MET Project to estimate teacher effects on students' performance on complex open-ended tasks in math and reading, as well as their growth mindset, grit, and effort in class. I find large teacher effects across this expanded set of outcomes, but weak relationships between these effects and performance measures used in current teacher evaluation systems including value-added to state standardized tests. These findings suggest teacher effectiveness is multidimensional, and high-stakes evaluation decisions are only weakly informed by the degree to which teachers are developing students' complex cognitive skills and social-emotional competencies. [ABSTRACT FROM AUTHOR]

In recent years, states and districts have responded to federal incentives and pressure to institute major reforms to their teacher evaluation systems. The passage of the Every Student Succeeds Act in 2015 now provides state policymakers with even greater autonomy to redesign existing evaluation systems. Yet, little evidence exists to inform decisions about two key system design features: teacher performance measure weights and performance ratings thresholds. Using data from the Measures of Effective Teaching study, we conduct simulation-based analyses that illustrate the critical role that performance measure weights and ratings thresholds play in determining teachers’ summative evaluation ratings and the distribution of teacher proficiency rates. These findings offer insights to policymakers and administrators as they refine and possibly remake teacher evaluation systems.

Teacher teams are increasingly common in urban schools. In this study, we analyze teachers’ responses to teams in six high-poverty schools. Teachers used two criteria to assess teams’ goodness of fit in meeting the demands of their work: whether their teams helped them teach better and whether the team contributed to a better school. Their responses differed notably by school, depending largely on the principal’s approach to implementation. In the three schools where teachers assessed teams favorably, principals set a meaningful purpose for teachers’ collaborative work, provided structural support and professional expertise for their deliberations, and established safe environments for teachers’ on-the-job growth.

In 2009, the New Teacher Project’s The Widget Effect documented the failure of U.S. public school districts to recognize and act on differences in teacher effectiveness. We revisit these findings by compiling teacher performance ratings across 24 states that adopted major reforms to their teacher evaluation systems. In the vast majority of these states, the percentage of teachers rated unsatisfactory remains less than 1%. However, the full distributions of ratings vary widely across states, with 0.7% to 28.7% rated below proficient and 6% to 62% rated above proficient. We present original survey data from an urban district illustrating that evaluators perceive more than 3 times as many teachers in their schools to be below proficient than they rate as such. Interviews with principals reveal several potential explanations for these patterns.

Despite the ubiquity and importance of glycans in biology, methods to probe their structures in cells are limited. Mammalian glycans can be modulated using metabolic incorporation, a process in which non-natural sugars are taken up by cells, converted to nucleotide-sugar intermediates, and incorporated into glycans via biosynthetic pathways. These studies have revealed examples in which glycan intermediates can be shunted through multiple pathways, and this complexity can be heightened in bacteria, as they can catabolize diverse glycans. We sought to develop a strategy that probes structures recalcitrant to metabolic incorporation and that complements approaches focused on nucleotide sugars. We reasoned lipid-linked glycans, which are intermediates directly used in glycan biosynthesis, would offer an alternative. We generated synthetic arabinofuranosyl phospholipids to test this strategy in Corynebacterium glutamicum and Mycobacterium smegmatis, organisms that serve as models of Mycobacterium tuberculosis. Using a C. glutamicum mutant that lacks arabinan, we identified synthetic glycosyl donors whose addition restores cell wall arabinan, demonstrating that non-natural glycolipids can serve as biosynthetic intermediates and function in chemical complementation. The addition of an isotopically labeled glycan substrate facilitated cell wall characterization by NMR. Structural analysis revealed that all the five known arabinofuranosyl transferases could process the exogenous lipid-linked sugar donor allowing for the full recovery of the cell envelope. The lipid-based probe could also rescue wild type cells treated with an inhibitor of cell wall biosynthesis. Our data indicate that surrogates of natural lipid-linked glycans can intervene in the cell’s traditional workflow, indicating biosynthetic incorporation is a powerful strategy to probe glycan structure and function.

We study the relationship between school organizational contexts, teacher turnover, and student achievement in New York City (NYC) middle schools. Using factor analysis, we construct measures of four distinct dimensions of school climate captured on the annual NYC School Survey. We identify credible estimates by isolating variation in organizational contexts within schools over time. We find that improvements in school leadership especially, as well as in academic expectations, teacher relationships, and school safety are all independently associated with corresponding reductions in teacher turnover. Increases in school safety and academic expectations also correspond with student achievement gains. These results are robust to a range of threats to validity suggesting that our findings are consistent with an underlying causal relationship.

Purpose: New teacher evaluation systems have expanded the role of principals as instructional leaders, but little is known about principals’ ability to promote teacher development through the evaluation process. We conducted a case study of principals’ perspectives on evaluation and their experiences implementing observation and feedback cycles to better understand whether principals feel as though they are able to promote teacher development as evaluators. Research Method: We conducted interviews with a stratified random sample of 24 principals in an urban district that recently implemented major reforms to its teacher evaluation system. We analyzed these interviews by drafting thematic summaries, coding interview transcripts, creating data-analytic matrices, and writing analytic memos. Findings: We found that the evaluation reforms provided a common framework and language that helped facilitate principals’ feedback conversations with teachers. However, we also found that tasking principals with primary responsibility for conducting evaluations resulted in a variety of unintended consequences which undercut the quality of evaluation feedback they provided. We analyze five broad solutions to these challenges: strategically targeting evaluations, reducing operational responsibilities, providing principal training, hiring instructional coaches, and developing peer evaluation systems. Implications: The quality of feedback teachers receive through the evaluation process depends critically on the time and training evaluators have to provide individualized and actionable feedback. Districts that task principals with primary responsibility for conducting observation and feedback cycles must attend to the many implementation challenges associated with this approach in order for next-generation evaluation systems to successfully promote teacher development.

We use matched employee–employer records from the teacher labor market to explore the effects of late teacher hiring on student achievement. Hiring teachers after the school year starts reduces student achievement by 0.042 SD in mathematics and 0.026 SD in reading. This reflects, in part, a temporary disruption effect in the first year. In mathematics, but not in reading, late-hired teachers remain persistently less effective, evidence of negative selection in the teacher labor market. Late hiring concentrates in schools that disproportionately serve disadvantaged student populations, contributing to challenges in ensuring an equitable distribution of educational resources for all students.

Researchers commonly interpret effect sizes by applying benchmarks proposed by Jacob Cohen over a half century ago. However, effects that are small by Cohen’s standards are large relative to the impacts of most field-based interventions. These benchmarks also fail to consider important differences in study features, program costs, and scalability. In this article, I present five broad guidelines for interpreting effect sizes that are applicable across the social sciences. I then propose a more structured schema with new empirical benchmarks for interpreting a specific class of studies: causal research on education interventions with standardized achievement outcomes. Together, these tools provide a practical approach for incorporating study features, costs, and scalability into the process of interpreting the policy importance of effect sizes.

We used self-report surveys to gather information on a broad set of non-cognitive skills from 1,368 eighth graders. At the student level, scales measuring conscientiousness, self-control, grit, and growth mindset are positively correlated with attendance, behavior, and test-score gains between fourth grade and eighth grade. Conscientiousness, self-control, and grit are unrelated to test-score gains at the school level, however, and students attending over-subscribed charter schools score lower on these scales than do students attending district schools. Exploiting admissions lotteries, we find positive impacts of charter school attendance on achievement and attendance but negative impacts on these non-cognitive skills. We provide suggestive evidence that these paradoxical results are driven by reference bias or the tendency for survey responses to be influenced by social context.

This article analyzes a coaching model focused on classroom management skills and instructional practices across grade levels and subject areas. We describe the design and implementation of MATCH Teacher Coaching among an initial cohort of 59 teachers working in New Orleans charter schools. We evaluate the effect of the program on teachers’ instructional practices using a block randomized trial and find that coached teachers scored 0.59 standard deviations higher on an index of effective teaching practices comprised of observation scores, principal evaluations, and student surveys. We discuss implementation challenges and make recommendations for researcher–practitioner partnerships to address key remaining questions.

Although previous research has shown that teacher coaching can improve teaching practices and student achievement, little is known about specific features of effective coaching programs. We estimate the impact of MATCH Teacher Coaching (MTC) on a range of teacher practices using a blocked randomized trial and explore how changes in the coaching model across two cohorts are related to program effects. Findings indicate large positive effects in Cohort 1 but no effects in Cohort 2. After ruling out explanations related to the research design, a set of exploratory analyses suggest that differential treatment effects may be attributable to differences in coach effectiveness, coaching dosage, and the focus of coaching across cohorts.

Purpose: We examine how uncertainty, both about students and the context in which they are taught, remains a persistent condition of teachers’ work in high-poverty, urban schools. We describe six schools’ organizational responses to these uncertainties, analyze how these responses reflect open- versus closed-system approaches, and examine how this orientation affects teachers’ work. Research Methods: We draw on interviews with a diverse set of 95 teachers and administrators across a purposive sample of six high-poverty, urban schools in one district. We analyzed these interviews by drafting thematic summaries, coding interview transcripts, creating data-analytic matrices, and writing analytic memos. Findings: We find that students introduced considerable uncertainty into teachers’ work. Although most teachers we spoke with embraced the challenges of their work and the expanded responsibilities that it entailed, they recognized that their individual efforts were not sufficient to succeed. Teachers consistently spoke about the need for organizational responses that addressed the environmental uncertainty of working with students from low-income families whose experience in school often has been unsuccessful. We describe four types of organizational responses—coordinated instructional supports, systems to promote order and discipline, socioemotional supports for students, and efforts to engage parents—and illustrate how these responses affected teachers’ ability to manage the uncertainty introduced by their environment. Conclusions: Traditional public schools are open systems and require systematic organizational responses to address the uncertainty introduced by their environments. Uncoordinated individual efforts alone are not sufficient to meet the needs of students in high-poverty urban communities.

We present new evidence on the relationship between teacher productivity and job experience. Econometric challenges require identifying assumptions to model the within-teacher returns to experience with teacher fixed effects. We describe the identifying assumptions used in past models and in a new approach that we propose, and we demonstrate how violations of these assumptions can lead to substantial bias. Consistent with past research, we find that teachers experience rapid productivity improvement early in their careers. However, we also find evidence of returns to experience later in the career, indicating that teachers continue to build human capital beyond these first years.

Most teacher layoffs during the Great Recession were implemented following inverse-seniority policies. In this paper, I examine the implementation of a discretionary layoff policy in Charlotte Mecklenburg Schools. Administrators did not uniformly lay off the most or least senior teachers but instead selected teachers who were previously retired, late-hired, unlicensed, low-performing, or nontenured. Using quasi-experimental variation within schools across grades, I then estimate the differential effects of teacher layoffs on student achievement based on teacher seniority and effectiveness. Mathematics achievement in grades that lost an effective teacher, as measured by principal evaluations or value-added scores, decreased 0.05 to 0.11 standard deviations more than in grades that lost an ineffective teacher. In contrast, teacher seniority has limited predictive power on the effects of layoffs. Simulation analyses show that the district selected teachers who were, on average, less effective than those teachers identified under an inverse-seniority policy, and also reduced job losses.

Parental involvement is correlated with student performance, though the causal relationship is less well established. This experiment examined an intervention that delivered weekly one-sentence individualized messages from teachers to the parents of high school students in a credit recovery program. Messages decreased the percentage of students who failed to earn course credit from 15.8% to 9.3%—a 41% reduction. This reduction resulted primarily from preventing drop-outs, rather than from reducing failure or dismissal rates. The intervention shaped the content of parent–child conversations with messages emphasizing what students could improve, versus what students were doing well, producing the largest effects. We estimate the cost of this intervention per additional student credit earned to be less than one-tenth the typical cost per credit earned for the district. These findings underscore the value of educational policies that encourage and facilitate teacher-to-parent communication to empower parental involvement in their children's education.

Extensive glycan microarray and structural analyses reveal that human intelectin-1 interacts selectively with microbial glycan epitopes through recognition of a terminal 1,2-diol group, an interaction that would be blocked in human glycans such as α-Neu5Ac. The glycans displayed on mammalian cells can differ markedly from those on microbes. Such differences could, in principle, be 'read' by carbohydrate-binding proteins, or lectins. We used glycan microarrays to show that human intelectin-1 (hIntL-1) does not bind known human glycan epitopes but does interact with multiple glycan epitopes found exclusively on microbes: β-linked D-galactofuranose (β-Galf), D-phosphoglycerol–modified glycans, heptoses, D-glycero- D-talo-oct-2-ulosonic acid (KO) and 3-deoxy-D- manno-oct-2-ulosonic acid (KDO). The 1.6-A-resolution crystal structure of hIntL-1 complexed with β-Galf revealed that hIntL-1 uses a bound calcium ion to coordinate terminal exocyclic 1,2-diols. N-acetylneuraminic acid (Neu5Ac), a sialic acid widespread in human glycans, has an exocyclic 1,2-diol but does not bind hIntL-1, probably owing to unfavorable steric and electronic effects. hIntL-1 marks only Streptococcus pneumoniae serotypes that display surface glycans with terminal 1,2-diol groups. This ligand selectivity suggests that hIntL-1 functions in microbial surveillance.

Evidence on the effect of extending the school day is decidedly mixed because of the stark differences in how schools use additional time. In this paper, I focus narrowly on the effect of additional time used for individualized tutorials. In 2005, MATCH Charter Public High School integrated two hours of tutorials throughout an extended day. The unanticipated implementation of this initiative and the school's admissions lottery allow me to use two complementary quasi-experimental methods to estimate program effects. I find that providing students with daily tutorials that are integrated into the school day and taught by full-time, recent college graduates increased achievement on tenth-grade English language arts exams by 0.15–0.25 standard deviations per year. I find no average effect in mathematics beyond the large gains students were already achieving, although quantile regression estimates suggest the tutorials raised the lowest end of the achievement distribution in mathematics.

We use matched employee-employer records from the teacher labor market to explore the effects of late teacher hiring on student achievement. Hiring teachers after the school year starts reduces student achievement by 0.042SD in mathematics and 0.026SD in reading. This reflects, in part, a temporary disruption effect in the first year. In mathematics, but not in reading, late-hired teachers remain persistently less effective, evidence of negative selection in the teacher labor market. Late hiring concentrates in schools that disproportionately serve disadvantaged student populations, contributing to challenges in ensuring an equitable distribution of educational resources across students.

Research has focused predominantly on how teachers affect students’ achievement on standardized tests despite evidence that a broad range of attitudes and behaviors are equally important to their long-term success. We find that upper-elementary teachers have large effects on self-reported measures of students’ self-efficacy in math, and happiness and behavior in class. Students’ attitudes and behaviors are predicted by teaching practices most proximal to these measures, including teachers’ emotional support and classroom organization. However, teachers who are effective at improving test scores often are not equally effective at improving students’ attitudes and behaviors. These findings lend empirical evidence to well-established theory on the multidimensional nature of teaching and the need to identify strategies for improving the full range of teachers’ skills.