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171.
Many short-duration science outreach interventions have important societal goals of raising science literacy and increasing the size and diversity of the science workforce. Yet, these long-term outcomes are inherently challenging to evaluate. We present findings from a qualitative research study of an inquiry-based, life science outreach program to K-12 classrooms that is typical in design and excellent in execution. By considering this program as a best case of a common outreach model, the "scientist in the classroom," the study examines what benefits may be realized for each participant group and how they are achieved. We find that K-12 students are engaged in authentic, hands-on activities that generate interest in science and new views of science and scientists. Teachers learn new science content and new ways to teach it, and value collegial support of their professional work. Graduate student scientists, who are the program presenters, gain teaching and other skills, greater understanding of education and diversity issues, confidence and intrinsic satisfaction, and career benefits. A few negative outcomes also are described. Program elements that lead to these benefits are identified both from the research findings and from insights of the program developer on program design and implementation choices. 相似文献
172.
The perceived spatiotemporal continuity of objects depends on the way they appear and disappear as they move in the spatial layout. This study investigated whether infants' predictive tracking of a briefly occluded object is sensitive to the manner by which the object disappears and reappears. Five-, 7-, and 9-month-old infants were shown a ball rolling across a visual scene and briefly disappearing via kinetic occlusion, instantaneous disappearance, implosion, or virtual occlusion. Three different measures converged to show that predictive tracking increased with age and that infants were most likely to anticipate the reappearance of the ball following kinetic occlusion. These results suggest that infants' knowledge of the permanence and nonpermanence of objects is embodied in their predictive tracking. 相似文献
173.
Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs 总被引:10,自引:0,他引:10
Early DM Maxwell KL Burchinal M Alva S Bender RH Bryant D Cai K Clifford RM Ebanks C Griffin JA Henry GT Howes C Iriondo-Perez J Jeon HJ Mashburn AJ Peisner-Feinberg E Pianta RC Vandergrift N Zill N 《Child development》2007,78(2):558-580
In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children. 相似文献
174.
This research examined adolescents' judgments about lying to circumvent directives from parents or friends in the moral, personal, and prudential domains. One hundred and twenty-eight adolescents (12.1-17.3 years) were presented with situations in which an adolescent avoids a directive through deception. The majority of adolescents judged some acts as acceptable, including deception regarding parental directives to engage in moral violations and to restrict personal activities. Other acts of deception were judged as unacceptable, including deception of parents regarding prudential acts, as well as deception of friends in each domain. In addition, lying to conceal a misdeed was negatively evaluated. Most adolescents thought that directives from parents and friends to engage in moral violations or to restrict personal acts were not legitimate, whereas parental directives concerning prudential acts were seen as legitimate. Results indicate that adolescents value honesty, but sometimes subordinate it to moral and personal concerns in relationships of inequality. 相似文献
175.
Do preadolescent sport self-concepts influence subsequent sport performance? Longitudinal data (Grades 3, 4, and 6) for young boys and girls (N= 1,135; mean age = 9.67) were used to test reciprocal effects model (REM) predictions that sport self-concept is both a cause and a consequence of sport accomplishments. Controlling prior sport performance (performance-based measures and teacher assessments), prior sport self-concept had positive effects on subsequent sport performance in both Grade 4 and Grade 6 and for both boys and girls. Coupled with previous REM studies of adolescents in the academic domain, this first test for preadolescents in the sport domain supports the generalizability of REM predictions over gender, self-concept domain, preadolescent ages, and the transition from primary to secondary school. 相似文献
176.
Subtypes, severity, and structural stability of peer victimization: what does latent class analysis say? 总被引:2,自引:1,他引:1
This study uses latent class analysis (LCA) to empirically identify victimization groups during middle school. Approximately 2,000 urban, public middle school students (mean age in sixth grade = 11.57) reported on their peer victimization during the Fall and Spring semesters of their sixth, seventh, and eighth grades. Independent LCA analyses at each semester yielded 3 victim classes based on victimization degree rather than type (e.g., physical vs. relational). The most victimized class always represented the smallest proportion of the sample, decreasing from 20% in sixth grade to 6% by the end of eighth grade. This victimized class also always reported feeling less safe at school concurrently and more depressed than others 1 semester later, illustrating the validity of the LCA approach. 相似文献
177.
Veenstra R Lindenberg S Zijlstra BJ De Winter AF Verhulst FC Ormel J 《Child development》2007,78(6):1843-1854
For this study, information on Who Bullies Who was collected from 54 school classes with 918 children (M age = 11) and 13,606 dyadic relations. Bullying and victimization were viewed separately from the point of view of the bully and the victim. The two perspectives were highly complementary. The probability of a bully-victim relationship was higher if the bully was more dominant than the victim, and if the victim was more vulnerable than the bully and more rejected by the class. In a bully-victim dyad, boys were more often the bullies. There was no finding of sex effect for victimization. Liking reduced and disliking increased the probability of a bully-victim relationship. 相似文献
178.
Marital conflict and conduct problems in Children of Twins 总被引:3,自引:0,他引:3
Harden KP Turkheimer E Emery RE D'Onofrio BM Slutske WS Heath AC Martin NG 《Child development》2007,78(1):1-18
The Children-of-Twins design was used to test whether associations between marital conflict frequency and conduct problems can be replicated within the children of discordant twin pairs. A sample of 2,051 children (age 14-39 years) of 1,045 twins was used to estimate the genetic and environmental influences on marital conflict and determine whether genetic or environmental selection processes underlie the observed association between marital conflict and conduct problems. Results indicate that genetic and nonshared environmental factors influence the risk of marital conflict. Furthermore, genetic influences mediated the association between marital conflict frequency and conduct problems. These results highlight the need for quasiexperimental designs in investigations of intergenerational associations. 相似文献
179.
Two language acquisition processes (comprehension preceding production of word order, the noun bias) were examined in 2- and 3-year-old children (n=10) with autistic spectrum disorder and in typically developing 21-month-olds (n=13). Intermodal preferential looking was used to assess comprehension of subject-verb-object word order and the tendency to map novel words onto objects rather than actions. Spontaneous speech samples were also collected. Results demonstrated significant comprehension of word order in both groups well before production. Moreover, children in both groups consistently showed the noun bias. Comprehension preceding production and the noun bias appear to be robust processes of language acquisition, observable in both typical and language-impaired populations. 相似文献
180.
Improbable or impossible? How children reason about the possibility of extraordinary events 总被引:1,自引:1,他引:0
The present study investigated the development of possibility-judgment strategies between the ages of 4 and 8. In Experiment 1, 48 children and 16 adults were asked whether a variety of extraordinary events could or could not occur in real life. Although children of all ages denied the possibility of events that adults also judged impossible, children frequently denied the possibility of events that adults judged improbable but not impossible. Three additional experiments varied the manner in which possibility judgments were elicited and confirmed the robustness of preschoolers' tendency to judge improbable events impossible. Overall, it is argued that children initially mistake their inability to imagine circumstances that would allow an event to occur for evidence that no such circumstances exist. 相似文献