姆咪特罗尔变形记

夏天里一个温暖的日子,姆咪谷下着细雨,因此大家决定在室内玩捉迷藏。小吸吸站在墙角,双手捂住鼻子,数到十,然后转过身来开始捉——先到平时大家躲着的地方去捉．接着到一些特别的地方去捉。     

物理建模教学模式简介

建模教学是近30年来美国物理教学改革中最成功的教学模式之一．以认知建模理论为基础,建模教学包含3个循环的阶段：建立模型、检验和完善模型、应用模型,旨在帮助学生深入、连贯地学习物理学的思想方法．     

给被雪压的果树解除重负

下大雪了, 怎么办？ 是用一杆难以耍动的矛 刺穿跳舞的,飘落的 大雪花,     

最危险的污染：核污梁的世界简史

【编者按】日本3．11大地震引发的福岛核电站核辐射灾难,已成地球人再度反思核“安全”的焦点,但很遗憾如果像往常那样,只局促于技术层面去反思,从长远看,毫无疑问,是无济于事的。让人类身陷囹圄的何啻技术,难道出路仍然是创造更好的技术？人类想改变一切,却往往不肯改变自己,自作孽却不自知。核灾难的历史本身,就用毁灭性的事实反复...     

我国“择校”现象的教育社会学阐释

义务教育阶段的择校问题不仅是社会各界反映强烈的热点问题,而且是影响义务教育公平性和均衡性的难点问题。教育社会学关注教育获得与社会分层的关系,运用教育选择功能理论、阶层优势与社会选择理论、教育成层理论对择校问题进行分析,可以使人们明确其产生的深层原因。要规范择校行为,使其成为促进义务教育公平、推动教育均衡发展的有力举措,政府必须加大实施义务教育均衡化的力度,改革现行择校制度,同时要大力发展多种类型的中学教育,为人的成才提供多种渠道。     

Applying computerized-scoring models of written biological explanations across courses and colleges: prospects and limitations

Our study explored the prospects and limitations of using machine-learning software to score introductory biology students’ written explanations of evolutionary change. We investigated three research questions: 1) Do scoring models built using student responses at one university function effectively at another university? 2) How many human-scored student responses are needed to build scoring models suitable for cross-institutional application? 3) What factors limit computer-scoring efficacy, and how can these factors be mitigated? To answer these questions, two biology experts scored a corpus of 2556 short-answer explanations (from biology majors and nonmajors) at two universities for the presence or absence of five key concepts of evolution. Human- and computer-generated scores were compared using kappa agreement statistics. We found that machine-learning software was capable in most cases of accurately evaluating the degree of scientific sophistication in undergraduate majors’ and nonmajors’ written explanations of evolutionary change. In cases in which the software did not perform at the benchmark of “near-perfect” agreement (kappa > 0.80), we located the causes of poor performance and identified a series of strategies for their mitigation. Machine-learning software holds promise as an assessment tool for use in undergraduate biology education, but like most assessment tools, it is also characterized by limitations.     

Surgeons as medical school educators: an untapped resource

Despite extensive experience teaching residents, surgeons are an untapped resource for educating medical students. We hypothesized that by involving surgeons as teachers earlier in the medical school curriculum, medical students' interest in surgery will increase and their opinions of surgeons will improve. Five programs designed to involve surgeons as educators in the medical school curriculum were implemented. The first program, started in 2008, introduced surgical faculty into the first-year medical student anatomy dissection laboratories. Other programs initiated in 2008 included: Surgical Clinical Correlates in Anatomy, which involved faculty teaching through cadaver surgery; Clinical Pathologic Conferences in Anatomy, a surgeon-led conference based on clinical cases; and a women's faculty-student mentorship program. Table Rounds, a surgeon-led anatomy review that used clinical scenarios to quiz students was begun in 2009. All five programs were successfully integrated into the medical school curriculum. While student opinion of surgeons as educators improved, there were no significant changes in student interest in surgery as a career nor change in performance on written examinations over the Anatomy content covered by the surgeons. Surgical faculty and trainees can be integrated into the medical school curriculum. Involving surgeons as educators earlier in the medical school curriculum may have longer term effects than could be observed in this study. At a minimum, the experience improved student opinion of surgeons as educators.     

A study assessing the potential of negative effects in interdisciplinary math-biology instruction

There is increasing enthusiasm for teaching approaches that combine mathematics and biology. The call for integrating more quantitative work in biology education has led to new teaching tools that improve quantitative skills. Little is known, however, about whether increasing interdisciplinary work can lead to adverse effects, such as the development of broader but shallower skills or the possibility that math anxiety causes some students to disengage in the classroom, or, paradoxically, to focus so much on the mathematics that they lose sight of its application for the biological concepts in the center of the unit at hand. We have developed and assessed an integrative learning module and found disciplinary learning gains to be equally strong in first-year students who actively engaged in embedded quantitative calculations as in those students who were merely presented with quantitative data in the context of interpreting biological and biostatistical results. When presented to advanced biology students, our quantitative learning tool increased test performance significantly. We conclude from our study that the addition of mathematical calculations to the first year and advanced biology curricula did not hinder overall student learning, and may increase disciplinary learning and data interpretation skills in advanced students.     

Harnessing technology to improve formative assessment of student conceptions in STEM: forging a national network

Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students' thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation-funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community.