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951.
This article concerns a lacuna in chemistry students' reasoning about chemical bonding. Although chemistry students are familiar with the charges that make up the atom––both positive and negative––they refer only to the attraction between unlike charges. Specifically, they ignore the repulsion between the positive nuclei. We named this disregard of repulsion the lacuna of repulsion. Repulsion is a crucial component in the force-based explanation of chemical bonding, presenting the bond as a dynamic equilibrium between attraction and repulsion electrical forces. We noticed this lacuna incidentally while interviewing chemistry students for a bigger project aimed at supporting students in understanding the force-based explanation of chemical bonding. This article describes our systematic qualitative study of the lacuna of repulsion and its impact on mental models of 23 high school chemistry students. Our findings show that students use six mental models, most of them built upon each other. Beginning from a simple mental model that describes the chemical bond as electrons, continuing with the including attraction forces, and completing with repulsion and a dynamic view of the bond. Only when one considers both attraction and repulsion forces and understands the dynamic balance between them is it possible to build the force-based dynamic mental model of chemical bonding.  相似文献   
952.
This study investigates the relationships between professional knowledge, self-concept, and interest of pre-service physics teachers. In order to support student learning and interest development alike, teachers need a profound professional knowledge and respective motivational orientations. Developing both professional knowledge and motivational orientations in teachers is therefore a key challenge of teacher education. Prior research has focused on the development of content knowledge (CK) and pedagogical content knowledge (PCK) within teacher education, but the role of motivational orientations such as self-concept and interest have mostly been neglected areas of study. As individuals develop domain-specific motivational orientations, they compare their achievement in an external frame to the achievement of their peers, and they compare their achievements in an internal frame across domains. The effects of these psychological processes on domain-specific motivational orientations are described by the generalized internal/external frame of reference model (GI/E model). We assessed the professional knowledge (CK and PCK) and motivational orientations (self-concept and interest) of N = 200 pre-service physics teachers from 12 teacher education institutes in Germany. To investigate the predictions of the GI/E model, we utilized structural equation modeling. In line with the GI/E model, the analysis revealed that pre-service teachers use social comparisons. Pre-service teachers with a higher CK/PCK also showed a higher CK/PCK self-concept. We also identified instances of internal comparisons as we found that a high level of CK corresponds with a lower PCK self-concept. While we could not identify the same effects from professional knowledge on interest, self-concept mediated the effects from professional knowledge on interest. The results suggest that interdependencies between professional knowledge and motivational orientation should be given more consideration in teacher education research and should also be addressed more explicitly in teacher education.  相似文献   
953.
This research examines factors influencing elementary science teacher learning as they participate in professional development with and enactment of educative curricula in comparison with learning following limited professional development and enactment of traditional curricula. Using a randomized cluster design (125 teachers and 2,694 students in 4th—5th grades) that met the What Works Clearinghouse standards without reservations, teacher learning was conceptualized using four outcomes. Data were analyzed using standard single-level multiple regression models and possible mediation models for the teacher outcomes were considered using piecewise multiple regression and path analytic approaches. Treatment group teachers experienced greater increases in content knowledge, views of science inquiry, beliefs about reform-based teaching, and teaching self-efficacy than comparison group teachers. The findings indicate that what teachers learn from the combination of professional development and teaching with educative curriculum varies according to what their knowledge and beliefs are on entering the experience. Surprisingly, high entry-level self-efficacy was associated not only with lower learning gains for the teachers, but also for their students. Finally, teachers' space science learning and that of their students are implicated as mediators of the positive effect of the professional development and educative curriculum enactment on teacher beliefs about reform science teaching. This work refines and extends a theoretical framework of teachers' participatory relationship with curricula.  相似文献   
954.
Numerous national reports have identified the importance of significantly improving pathways that begin with Latinx students enrolling in 2-year institutions and ultimately completing baccalaureate degrees in STEM fields at 4-year institutions. Many programs using multiple interventions have been designed, implemented, and studied to achieve this goal. To synthesize what has been learned from studies of these programs, this article presents a systematic review of published studies of programs designed to support Latinx student success in 2-year institutions and successful transfer to 4-year institutions, particularly for STEM majors. A total of 49 quantitative, 9 qualitative, and 16 mixed-methods studies published as reports, articles, or dissertations since 1980 were identified that met the criteria for the review. Studies covered a wide range of interventions, including mentoring, counseling, advising, study groups, tutoring, scholarships, orientations, career services, undergraduate research, articulation agreements, and transfer programs. Individually, these studies report positive influences on student success outcomes, including 2- and 4-year graduation, transfer to a 4-year institution, retention, and success in individual courses. However, the number of qualifying studies was surprisingly small, considering the importance of improving success of Latinx students and the length of time during which the problem has been repeatedly emphasized. Few interventions have been undertaken from explicitly assets-based perspectives or theoretical frameworks. The lack of explicit frameworks underlying interventions—combined with a sole/primary focus on students—suggests many interventions were approached from a deficit-based perspective. Further, the study found no pattern of replication studies that might confirm effectiveness of potentially promising interventions. Based on our analysis of evaluations presented in the studies, it does not appear that the research community has developed agreed-upon methods to evaluate commonly agreed-upon outcomes. Finally, no intervention has been sufficiently supported that widespread implementation could be recommended.  相似文献   
955.
956.
957.
The need for science communication programs is matched with the need for program evaluation. This case study is an evaluation of the “Decoding Science” program (DSP) [Rodgers et al. (2018). Science Communication, 40(1), 3–32], a science communication training program, and examines key experiential-learning themes [Kolb, D. A. (1984). Experiential learning: Experience as the source of learning and development. Englewood Cliffs, NJ: Prentice-Hall]. Specifically, we discuss the program's emphasis on learning that science communication is a process that (a) is continual, (b) involves conflict resolution, (c) requires adaptation to the world, (d) requires environmental interaction, and leads to (e) knowledge creation. Additionally, we discuss our analysis of student feedback. Results suggest that the DSP successfully utilizes experiential learning to facilitate the learning of science communication techniques and that future evaluations can lead to the development and improvement of science communication training programs.  相似文献   
958.
Gendered patterns in mathematics and science interest emerge in early childhood, develop over time, and ultimately reflect advanced course selection in secondary education. During the crucial time adolescents become aware of their strengths and interests and specialize accordingly, they get the opportunity to participate in out-of-school learning programs such as mathematics and science competitions. This raises the question whether mathematics and science competitions contribute to gender equity by equally promoting female and male interests. In this article, we present a systematic review on gender differences and the mechanisms explaining success and failure in mathematics and science competitions. On an international level, we found large gender differences regarding participation in all Olympiads with the exception of the biology Olympiad. In fairs and national Olympiads, overall participation rates were not gendered as such, but females preferred biology topics whereas males preferred physics related topics. Male and female achievement in fairs was comparable, but males clearly outperformed female participants at the Olympiads, with the smallest differences in the biology Olympiad. Variables and theoretical frameworks explaining participation and achievement and the role of gender in mathematics and science competitions are discussed. We suggest that gender stereotypes, through their influence on self-concept and interest, play an important role in the mechanisms resulting in low female participation rates in and beyond mathematics and science competitions (especially in physics and chemistry). The mechanisms we found explaining female representation during a national selection competition might be considered as reflecting those in female mathematics or science careers and could thus serve as food for thought on countering the gender gap in mathematics and science.  相似文献   
959.
The increased use of Attention Deficit/Hyperactivity Disorder (ADHD) medication by children has led to growing concerns. In a previous study, we found that many of the teachers that were interviewed about ADHD spontaneously associated ADHD with medication. The present study is a qualitative reanalysis of what precisely these 30 primary school teachers had spontaneously said about medication in our previous semi‐structured interviews on ADHD. Almost all respondents had experience with pupils taking ADHD medication. The majority of spontaneously mentions medication as the treatment of ADHD. Attitudes towards ADHD medication use by pupils are mainly ambivalent, but more positive than negative effects of medication are reported. However, what teachers say about ADHD medication is often not based on sound information; their attitudes tend to be formed by personal experiences rather than founded on professional and scientific sources. We conclude from our analysis that it will be in the interest of reducing the number of children on ADHD medication that teachers have good access to verified and up‐to‐date information on ADHD and medication so that they are better supported in making evidence‐based pedagogical judgments.  相似文献   
960.
A random sample of 1,000 Nationally Certified School Psychologists were mailed a 17‐item survey about treatment integrity. A total of 132 responded and answered questions about the importance of treatment integrity data for tiered interventions and the frequency and methods used to measure treatment integrity in one‐to‐one and problem‐solving team consultation. Ninety‐eight percent agreed that treatment integrity data were critical for tiered interventions. However, only 7% in one‐to‐one consultation and 0% in team consultation reported it was “always” collected. Respondents identified barriers of time, workload, system factors, and staff knowledge as explanations for why there was a gap between belief and practice. The participant responses were compared to those from a 2008 survey and found to be almost unchanged. Issues associated with decision‐making when treatment integrity data are lacking and recommendations for improving the assessment and reporting of treatment integrity are discussed.  相似文献   
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