Do students learn what they teach when generating teaching materials for others? A meta-analysis through the lens of learning by teaching

Students can generate teaching materials for others. However, solid evidence of the learning effect for the student creating the material is needed. This meta-analysis aims to explore current evidence of the learning-by-teaching potential effect on students’ learning of the content they teach. A total of 23 articles were included in the meta-analysis, providing 62 comparisons between an intervention in which students were required to create a teaching material and an alternative condition. Possible moderators were examined as well (i.e., product, educational level, content area, and access to source material). Results show statistically significant differences in favour of creating teaching materials when compared to business-as-usual or alternative interventions, with an overall effect of 0.17. However, the type of product and the access to source material significantly moderate the findings. Audio-visual and visual materials considerably outperform textual materials. Having no access to the source material is better than having full access to it. No publication bias was detected. However, the type of control group moderates the findings: creating teaching materials shows a significant effect when compared to nonbeneficial interventions rather than to other expected beneficial interventions. Nonbeneficial interventions refer to business-as-usual or alternative interventions that are not expected to influence the outcome much, while beneficial interventions are those that are known or expected to have a positive effect. The findings are discussed based on the different views on the underlying learning-by-teaching mechanisms. Limitations as well as implications for practice, policy, and future research are underlined.     

AFE变频器在船舶电力推进电机控制中的应用

为有效改善船舶电力推进系统电能质量和能量反馈,将有源前端(Active Front End,AFE)变频器应用于船舶电力推进电机控制.根据船舶电力推进系统的特点,选择基于电流内环前馈解耦控制的直接电流控制方法,并对AFE变频器的独立控制和联合控制方式进行研究.用MATLAB/Simulink对这两种方式进行仿真.分析仿真结果,得出这两种控制方式分别适应的电力推进船舶类型.     

运动改善老年抑郁的研究现状

老年抑郁是老年群体中患病率相当高的一种精神障碍,抑郁带给人类社会的危害性及其严重。因此,老年抑郁症治疗的研究受到国内外研究者们的广泛关注。研究对运动改善老年抑郁样行为及其内在机制进行综述。     

论媒体在老龄社会中的政治责任

我国人口的老龄化,已成为关系国计民生的重要问题.发挥媒体在老龄化社会中时政宣传、倡导风尚、反映诉求、引导热点等作用,以高度的责任感办好适应老龄社会的媒体,是媒体人义不容辞的政治责任.     

道路沥青使用过程中水老化试验研究

在研究沥青材料热氧老化规律的基础上,为进一步模拟路面实际状态,在长期老化试验中引入了水的因素.采用加水的PAV（压力老化容器）试验模拟沥青在寿命期的老化过程,以2个SHRP性能指标车辙因子G＊/sinδ和劲度模量S（t）分别表示沥青的高温和低温性能,并用90#泰国沥青、90#改性沥青和70#壳牌沥青进行试验.结果表明：在水、温度和氧的共同作用下,水对高温性能指标G＊/sinδ产生显著影响,所以水老化使沥青的高温性能急剧衰退,而对低温性能的影响并不显著.加水的PAV试验综合考虑了水、温度和氧气等环境因素的作用,能够提高模拟试验的精确性,更好地模拟沥青路面使用寿命期的长期老化过程.     

论"健康老龄化"与老年体育

体育在"健康老龄化"这一社会系统工程的实现中具有积极的现实意义.采取切合实际的策略与手段是推进老年体育发展,促进"健康老龄化"实现的有力保障.     

Introductory statistics in the garden

This article describes four semesters of introductory statistics courses that incorporate service learning and gardening into the curriculum with applications of the binomial distribution, least squares regression and hypothesis testing. The activities span multiple semesters and are iterative in nature.     

Engineering students’ experiences of interactive teaching in calculus

This study reports on an educational development initiative where peer instruction was used instead of traditional lectures in a calculus course for first-year engineering students. The aim of the study was to explore students’ experiences of this method. Data were collected by means of an open-ended questionnaire on two occasions: early and late in the course. The data were analyzed with an inductive content analysis. The findings comprise three qualitatively different ways to experience the interactive teaching method in calculus: (1) enthusiasm, (2) nuanced skepticism and (3) aversion. The categories differed regarding emotional reactions to the teaching, experiences of learning, conceptions of teaching and learning, and experiences of meaningfulness. Many students expressed enthusiasm for learning with peer instruction and noted that the method gave both teachers and students feedback on what students have difficulties with. These students perceived that they were responsible for their own learning. Other students experienced that peer instruction had some advantages and disadvantages, and preferred a mix between traditional lectures and peer instruction sessions. They seemed to believe that teachers and students share responsibility for learning. Some students expressed an aversion for peer instruction and the method seemed to challenge their beliefs of how teaching and learning is best conducted. Our study illustrates that educational development initiatives, even though based on research on student learning, do not benefit all students. One of the major obstacles seems to be that students’ underlying beliefs regarding teaching and learning may be counterproductive to the ideas behind the educational initiative. We suggest that beliefs regarding teaching and learning need to be addressed when introducing new teaching and learning methods.     

Manipulating cognitive engagement in preparation-to-collaborate tasks and the effects on learning

While collaborating with a peer can be highly beneficial for learning, more work is needed to understand how instructional activities in collaborative contexts should be designed so as to maximize learning outcomes. To address this, we investigated the impact of different types of preparatory and cognitively engaging tasks on learning from collaborating, using a 2 × 2 experimental study conducted in situ in four introductory psychology classes. We compared individual preparation versus no-preparation and “active” versus “constructive” tasks. A dyadic multilevel analysis showed that preparation prior to collaborating led to better deep learning outcomes, but that the type of preparation did not have a significant effect. We include an exploratory analysis of student dialogues during collaboration to further interpret our findings. We propose that a cognitively engaging preparation phase may lead to better learning because it encourages students to collaborate constructively even when the type of task does not elicit such engagement.     

主动进气格栅技术研究

随着主动进气格栅技术在汽车上的逐步使用,主动进气格栅的技术优势逐步体现,文章阐述了主动进气格栅对整车行驶阻力的优化和整车热控制的相关影响,并以线性回归模型的方法对主动进气格栅的标定方法进行了初步探索。