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931.
Research has established that adolescents both befriend peers based on their academic achievement and adjust their own achievement to that of their friends’ over time. However, these processes may be different for ethnic minority students, because some of them may adhere to an oppositional culture that rejects striving for academic success. We examine respective differences between self-identified ethnic minority and majority students using longitudinal social network analysis (stochastic actor-oriented models) in a sample of 1175 students (aged 13) from 12 grade-level networks in Germany secondary schools. Among the students, we find that academically successful students in particular prefer friends with high grades, but that students with poor grades exert more social influence on their friends to adjust their performance. Moreover, while minority students are indeed less inclined to select friends with higher grades, both ethnic majority and minority youth prefer friends with similar academic achievement and are similarly influenced by their friends’ achievement. However, social influence is stronger from same-ethnic than from inter-ethnic friends. In sum, there is mixed evidence for an oppositional culture among ethnic minority students in our sample.  相似文献   
932.
Play is a behavioral phenomenon most commonly observed in the young of both solitary and social species. Documentation of play in cetaceans varies across species and settings. Cetacean play behavioral repertoires include a broad range of actions, such as the manipulation of diverse objects, blowing bubbles, chasing conspecifics, and swimming in spirals through the water. As is common in research on animal play, cetacean play has been grouped into categories by its form, including locomotor play, object play, and different variations of social play, such as affiliative games, play fighting, and socio-sexual play. Research has primarily focused on recording the topography of cetacean play and the demographics of the individuals engaging in play. However, these classifications are insufficient to address the possible developmental and societal functions of cetacean play behaviors, or the mechanisms with which play behaviors are spread between conspecifics and acquired by young members of cetacean populations. This article applies several developmental and social learning theories in order to organize current knowledge and guide future research.  相似文献   
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935.
Policies aiming to improve educational outcomes are typically based on academic testing data. However, such data only reflect the performance of students who completed the tests. It is possible that students who were absent have shared characteristics. The proportion of students absent out of all eligible school students and whether they have shared characteristics has not been investigated, as this is only possible through the use of linked administrative data. Participants were born in Western Australia in 1994 and 1995, and their birth records were linked to participation status in the Year 9 academic tests to determine the proportion of students who were absent. Logistic regression was conducted to investigate characteristics which predicted absence on test day. A proportion of non-Aboriginal (3.2 %) and Aboriginal students (21.9 %) were absent on test day. Risk factors which predicted the absence included contact with Child Protection and Family Services, history of maternal mental health problems, and fathers aged below 20 years at the time of their child’s birth. A significant proportion of students was absent and therefore not represented in academic achievement information. These students were more likely to have experienced adverse events and therefore are not randomly absent. As these data are typically used to inform policies which aim to improve educational outcomes, they may lack the necessary information to adequately address the complex needs of students who are absent on test day. However, findings suggest that service providers, as well as schools may play an important role in encouraging participation in school.  相似文献   
936.
937.
This study describes a comparison of how worked examples in selected textbooks from England and Shanghai presented possible learning trajectories towards understanding linear function. Six selected English textbooks and one Shanghai compulsory textbook were analysed with regards to the understanding required for pure mathematics knowledge in linear function. Understanding was defined as being at five levels: Dependent Relationship, Connecting Representations, Local Properties Noticing, Object Analysis and Inventising. These levels were developed by examining the most prominent theories from the existing literature on understanding function. Findings suggested that the English textbooks constrained the structural aspect of understanding linear function due to a point-to-point view of function, while the Shanghai textbook which focussed on a variable view of function overemphasised the algebraic approach. The discussion explored the drawbacks to each approach and what teachers or textbook writers could do to balance these two approaches in order to facilitate students’ understanding towards a structural view of linear function.  相似文献   
938.
The concepts and instruments required for the teaching and learning of geometric optics are introduced in the didactic process without a proper didactic transposition. This claim is secured by the ample evidence of both wide- and deep-rooted alternative concepts on the topic. Didactic transposition is a theory that comes from a reflection on the teaching and learning process in mathematics but has been used in other disciplinary fields. It will be used in this work in order to clear up the main obstacles in the teaching-learning process of geometric optics. We proceed to argue that since Newton’s approach to optics, in his Book I of Opticks, is independent of the corpuscular or undulatory nature of light, it is the most suitable for a constructivist learning environment. However, Newton’s theory must be subject to a proper didactic transposition to help overcome the referred alternative concepts. Then is described our didactic transposition in order to create knowledge to be taught using a dialogical process between students’ previous knowledge, history of optics and the desired outcomes on geometrical optics in an elementary pre-service teacher training course. Finally, we use the scheme-facet structure of knowledge both to analyse and discuss our results as well as to illuminate shortcomings that must be addressed in our next stage of the inquiry.  相似文献   
939.
This study examined the effectiveness of 3 curriculum interventions focused on strengthening children’s ability to solve area measurement problems and explored the instructional perspectives of the instructor who implemented the interventions. The interventions involved various degrees of emphasis on area measurement and knowledge of 2-dimensional geometry. Participants were 131 fourth graders, recruited from a city in northern Taiwan, and 1 instructor. The results confirmed the effectiveness of an enriched curriculum integrating knowledge of 2-dimensional geometry in enhancing children’s conceptual understanding of area measurement. The group that received the enriched curriculum outperformed the other groups that received the curricula stressing only 2-dimensional geometry or numerical calculations for area measurement in solving the area problems requiring mathematical judgments and explanations. The curriculum also facilitated children’s reasoning in distinguishing between the perimeter and area of a rectangle, which required higher-order mathematical thinking. Interview data revealed that approximately all children from the 3 intervention groups could identify the mathematical subject-matter components highlighted in the curricula. Interviewees tended to consider the use of formulae to solve area measurement problems to be important, despite some differences in learning gains among the 3 groups. In interviews, the participating instructor revealed a change of perspective regarding the importance of offering students opportunities for manipulation and geometric operations when teaching area measurement, prompted by curriculum enactment.  相似文献   
940.
Reported are the results of a multiyear study in which reading comprehension and writing were integrated within an in-depth science instructional model (Science IDEAS) in daily 1.5 to 2 h daily lessons on a schoolwide basis in grades 3–4–5. Multilevel (HLM7) achievement findings showed the experimental intervention resulted in significant and consistent direct effects in grades 3–4–5 and complementary transfer effects in grades 6–7 on both ITBS Science (+1.08 Grade Equivalent Units [GE]) and ITBS Reading (+.57 GE). Discussed are implications of the findings and related research for changing grade K-5 curriculum policy to allocate increased instructional time for integrated science instruction.  相似文献   
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