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851.
During the 1980s, topics evident in the class size research included class size and children’s achievement, children’s behavior and affect, outcomes for different groups of children, teacher satisfaction and stress, the organization of instruction, and cost effectiveness. A New Zealand review tracing through the approaches to class size research indicated that the research methods used to investigate class size had become increasingly complex. In the 1990s, these topics continue to be addressed, with an increasing emphasis on the features and impact over time of smaller classes, and on the economics of schooling. In New Zealand in the late 1980s, a 1 : 20 teacher to pupil ratio policy was introduced for junior classes. The current staffing ratio in junior classes is 1 : 23. This summary review of the literature on class size highlights some issues and complexities arising from the international research and research within the New Zealand context.  相似文献   
852.
Many enzymes and proteins have metal ions at their active sites that play key roles in catalysis. An important goal of an interdisciplinary field like bioinorganic chemistry is the development of small inorganic coordination complexes that not only reproduce structural and spectroscopic features, but also function in a manner similar to their natural counterparts. To highlight this burgeoning field, some selected results on synthetic modelling of (i) the electronic structure of manganese cluster of photosystem II and (ii) functional modelling of the dinuclear copper enzyme tyrosinase are described in this article.  相似文献   
853.
Little is known about how children's value priorities develop over time. This study identifies children's value priority profiles and follows their development during middle childhood. Australian children (N = 609; ages 5–12 at Time 1) reported their values over 2 years. Latent Transition Analysis indicated four profiles: Social-Focus, Self-Focus, Growth-Focus and Undifferentiated. Within person development was characterized by profile stability or transfer to the Social-Focus profile. Younger children were more likely to have an Undifferentiated profile (or Self-Focus among boys) than older ones. Girls were more likely to have a Social-Focus profile or transfer to it, and less likely to have a Self- or Growth-Focus profile than boys. Social-Focus profile membership over time predicted more prosocial and less aggressive behavior.  相似文献   
854.
This study examined two possible mechanisms, evocative gene–environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers’ negative reactivity at 18 months was positively associated with adoptive parents’ over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children’s negative reactivity at 18 months. This study provides critical evidence for “child on parent” effects.  相似文献   
855.
Electronic games are popular and many children spend much time on this activity. Here we investigate whether the quantity of time children spend on gaming is related to their social development, making this the first study to examine this relationship in children. We examine prospective relations between time spent gaming and social competence in a community sample of Norwegian 6 year olds (n = 873) followed up at ages 8, 10, and 12, controlling for socioeconomic status, body mass index, and time spent gaming together with friends. Results revealed that greater social competence at both 8 and 10 years predicted less gaming 2 years later and that more age-10 gaming predicted less social competence at age 12 but only among girls.  相似文献   
856.
Grit has been defined as passionate perseverance toward long-term challenging goals and it is associated with various positive outcomes for youth, including academic achievement. However, less is known about these associations for the two facets of grit (i.e., perseverance of effort, consistency of interest) and few studies have examined the link between grit and perceived social support. The present study examined the group-level demographic differences (i.e., gender, grade, socioeconomic status, and special education status) of grit in a high school sample (N = 1,077). In addition, direct associations between grit and perceived social support from multiple sources (i.e., teacher, classmate, parent) were examined, as well as a potential enhancing effect of social support as a moderator of the relation between grit and academic achievement. Results indicated positive associations among grit and its facets with social support from parents and classmates. Furthermore, the positive relation between grit and achievement was stronger for students reporting high social support from teachers, but not other sources (i.e., classmates, parents). Practical and theoretical implications for promoting student success are discussed.  相似文献   
857.
School districts and other service providers are increasingly aware of the substantial mental health needs of students experiencing family homelessness. Past findings are mixed regarding whether homelessness conveys unique risk beyond the risks associated with extreme poverty. With prospective longitudinal data on homelessness experiences across childhood, we utilized latent profile analysis as a person-centered approach to conceptualizing mental health outcomes in adolescence for 3,778 youth. We considered literal family homelessness as well as families living doubled-up, and we employed propensity score matching to identify a comparison group of nonhomeless students balanced across a range of covariates to address systematic bias. Results indicated that students who experienced literal homelessness during childhood were significantly less likely to demonstrate profiles of resilience in mental health functioning. We considered our approach and findings in light of challenges and opportunities particularly relevant to the school context.  相似文献   
858.
The demand for upper-level undergraduate dissection-based anatomy courses is growing, as professional programs require more advanced anatomy training prior to matriculation. To address this need, Indiana University School of Medicine (IUSM) partnered with Indiana University-Purdue University Indianapolis—a large, urban, life science-focused campus nearby to IUSM—to offer an undergraduate, dissection-based course in regional gross anatomy. Because this is a new course, a deeper post-course evaluation of student perceptions was conducted using Q methodology. In this study, Q methodology was used to evaluate student views of the overall course structure, pre-laboratory materials and activities, assessments, and quality of instruction. Of the 15 students in the spring semester 2018 cohort, 80% (n = 12) participated in the evaluation, and 10 of those students followed up with written explanations for their rationale in selecting the four statements with which they most strongly agreed and disagreed. The Q methodology sorted the students into one of three statistically significant groups: Motivated Dissectors (n = 6), Traditional Students (n = 3), and Inspired Learners (n = 3). Motivated Dissectors and Inspired Learners felt strongly that the course did not encourage self-directed learning and that the pre-laboratory materials were not adequate to prepare them for quizzes. Traditional Students, however, disagreed, having a favorable opinion of the pre-laboratory materials, even though this group felt most strongly that the amount of material covered in the course was overwhelming. This study demonstrates the utility of Q methodology to evaluate courses to elucidate student perspectives and inform future course modifications.  相似文献   
859.
The degree to which teachers' perceptions of a student can be distorted by characteristics indigenous to teachers, as well as students, were investigated to determine whether teachers would initiate a referral for special education. Sixty-five teachers volunteered for participation. Twenty-seven of them were experienced, having had their own classrooms in a public school. Thirty-eight were preservice student teachers who had not yet had their own classrooms. Teachers were evaluated to have had either an internal or external locus of control and were judged to have had either a high or low opinion of self according to either of two separate scales. After viewing two video tapes of two elementary-aged students (one student was severely emotionally disturbed [SED] and the other non-SED), teachers rated the children on several child characteristics and referral questions. Results revealed that the locus of control and self-esteem of teachers, in conjunction with teaching experience and a child's characteristics, can predict teachers' inclinations to refer children. Findings point to the need to place greater care in the initiation of referrals. © 1997 John Wiley & Sons, Inc.  相似文献   
860.
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