The small-gain theorem,the passivity theorem and their equivalence

Two small-gain theorems and a passivity theorem yielding stability results for general feedback systems are shown to be equivalent.     

Instructional practices in secondary science: How teachers achieve local and standards-based success

This article reports on analyses of the instructional practices of six middle- and high-school science teachers in the United States who participated in a research-practice partnership that aims to support reform science education goals at scale. All six teachers were well qualified, experienced, and locally successful—respected by students, parents, colleagues, and administrators—but they differed in their success in supporting students' three-dimensional learning. Our goal is to understand how the teachers' instructional practices contributed to their similarities in achieving local success and to differences in enabling students' learning, and to consider the implications of these findings for research-practice partnerships. Data sources included classroom videos supplemented by interviews with teachers and focus students and examples of student work. We also compared students' learning gains by teacher using pre–post assessments that elicited three-dimensional performances. Analyses of classroom videos showed how all six teachers achieved local success—they led effectively managed classrooms, covered the curriculum by teaching almost all unit activities, and assessed students' work in fair and efficient ways. There were important differences, however, in how teachers engaged students in science practices. Teachers in classrooms where students achieved lower learning gains followed a pattern of practice we describe as activity-based teaching, in which students completed investigations and hands-on activities with few opportunities for sensemaking discussions or three-dimensional science performances. Teachers whose students achieved higher learning gains combined the social stability characteristic of local classroom success with more demanding instructional practices associated with scientific sensemaking and cognitive apprenticeship. We conclude with a discussion of implications for research-practice partnerships, highlighting how partnerships need to support all teachers in achieving both local and standards-based success.     

A refined definition of structure in teaching

More on structure in teaching. Will the order of presentation of material influence production of logical relationships?     

在线学习的理论与实践

本刊今年第3期刊登了记者对国际知名远程教育专家、加拿大阿萨巴斯卡大学特里·安德森教授的专访。安德森教授在专访中提及他和同事法希·埃劳米的新著《在线学习的理论与实践》,“希望能得到我们中国朋友的青睐和欣赏”。该书收录了16篇论文,作者全部是阿萨巴斯卡大学的教师和研究者,也都是20世纪90年代中期以来阿萨巴斯卡大学为了应对日益裁减的政府资助和生源的锐减而进行大规模教育改革的实践者和见证人,这些论文既有经验总结又有前瞻性的思考,对我国的远程教育事业不无借鉴价值。鉴于此,本刊特邀肖俊洪先生谨将该书两位主编所撰写的“引言”中的有关全书内容概要的部分译成中文,以飨读者。     

Raising Standards In Natural History Dioramas: The Background Painting of James Perry Wilson

Abstract James Perry Wilson transformed the subjective methodology of diorama background painting into a more objective practice by replacing an emotional and interpretive model with one based on the science of optics and other supportable references. He also succeeded in creating an overall mood in each of his diorama paintings. This article documents the step by step process of Wilson's methods. Wilson's two methods for documenting the site chosen for the diorama were: a plein air field painting, and panoramic photographs. At the museum, he created a complete scale model of the diorama and its background, accurate in all aspects, though miniature. On the full‐scale diorama background, a charcoal underdrawing preceded the painting. The sky was painted first, next the horizon, then the mid‐range distances, and finally the foreground. Each stage increased in colorvalue contrast and in resolution of detail. Wilson's mastery is most evident in the “tie‐up,” where the painted background meets the three‐dimensional foreground.     

DREW,David E. 1996. Aptitude Revisited: Rethinking Math and Science Education for America's Next Century

International Review of Education -     

Writing week-journals to improve the writing quality of fourth-graders’ compositions

Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing.     

Barriers to environmental education: How do teachers’ perceptions in rural Ecuador fit into a global analysis?

Abstract

We identified 48 barriers to teaching environmental education reported by teachers in global literature and compared frequency to empirical data we collected from rural Ecuador, part of an understudied region and continent. We utilized Q methodology and interviews with 25 (78%) teachers at 6 schools to identify and categorize barriers. Perceptions of barriers ranked by Ecuadorian teachers were statistically classified into three factors: logistical (associated with fieldtrips, time, and money); training and lack of government support; and attitudinal (associated with student disinterest). In contrast, barriers related to student testing and controversial topics were only reported in more developed countries. Results enable region-specific recommendations.