What Is a Fraction? Developing Fraction Understanding in Prospective Elementary Teachers

Classroom teachers need a well‐developed deep understanding of fractions and pedagogic practices so they can provide meaningful experiences for students to explore and construct ideas about fractions. This study sought to examine prospective elementary teachers' understandings of fraction by focusing specifically on their use of fractions meanings and interpretations. Results indicated that prospective elementary teachers bring with them to their final methods course a limited understanding of fractions and that experiences in methods courses resulted only in minor improvement of those limited understandings. The limited part‐whole understanding of fractions that prospective elementary teachers entered the course with was resilient. The implications of this study suggest a need for prospective elementary teachers to continue to develop their conceptual understanding of fractions and for changes to the content and instructional strategies of mathematics content courses designed for prospective elementary teachers.     

Characteristics of Second Graders' Mathematical Writing

This study compared the characteristics of second graders' mathematical writing between an intervention and comparison group. Two six‐week Project M2 units were implemented with students in the intervention group. The units position students to communicate in ways similar to mathematicians, including engaging in verbal discourse where they themselves make sense of the mathematics through discussion and debate, writing about their reasoning on an ongoing basis, and utilizing mathematical vocabulary while communicating in any medium. Students in the comparison group learned from the regular school curriculum. Students in both the intervention and comparison groups conveyed high and low levels of content knowledge as indicated in archived data from an open‐response end‐of‐the‐year assessment. A multivariate analysis of variance indicated several differences favoring the intervention group. Both the high‐ and low‐level intervention subgroups outperformed the comparison group in their ability to (a) provide reasoning, (b) attempt to use formal mathematical vocabulary, and (c) correctly use formal mathematical vocabulary in their writing. The low‐level intervention subgroup also outperformed the respective comparison subgroup in their use of (a) complete sentences and (b) linking words. There were no differences between groups in their attempt at writing and attempts at and usage of informal mathematical vocabulary.     

Next Generation Science Standards: A National Mixed‐Methods Study on Teacher Readiness

Next Generation Science Standards (NGSS) science and engineering practices are ways of eliciting the reasoning and applying foundational ideas in science. As research has revealed barriers to states and schools adopting the NGSS, this mixed‐methods study attempts to identify characteristics of professional development (PD) that will support NGSS adoption and to improve teacher readiness. In‐service science teachers from across the nation were targeted for the survey and responses represented 38 states. Research questions included: How motivated and prepared are in‐service 7–12 teachers to use NGSS science and engineering practices? What is the profile of 7–12 in‐service teachers who are motivated and feel prepared to use NGSS science and engineering practices? The study revealed that teachers identified engineering most frequently as a PD need to improve their NGSS readiness. High school teachers rated themselves as more prepared than middle school and all teachers who use Modeling Instruction expressed higher NGSS readiness. These findings and their specificity contribute to current knowledge, and can be utilized by districts in selecting PD to support teachers in preparing to implement the NGSS successfully.     

Beliefs,Practical Knowledge,and Context: A Longitudinal Study of a Beginning Biology Teacher's 5E Unit

The purpose of this three‐year case study was to understand how a beginning biology teacher (Alice) designed and taught a 5E unit on natural selection, how the unit changed when she took a position in a different school district, and why the changes occurred. We examined Alice's developing beliefs about science teaching and learning, practical knowledge, and perceptions of school context in relation to the 5E unit. Data sources consisted of interviews, classroom observations, and lesson materials. We found that Alice placed more emphasis on the explore phase, less emphasis on the engage and explain phases, and removed the elaborate phase over time. Alice's beliefs about science teaching and learning acted as a filter for making sense of practical knowledge and perceptions of context. Although her beliefs were student centered, they aligned with discovery learning in which little intervention from the teacher is required. We discuss how her beliefs, practical knowledge, and perceptions of context explained the changes in her practice. This study sheds insight into the nature of beliefs and how they relate to the 5E lesson phases, as well as the different lenses for viewing the 5E instructional model. Implications for science teacher preparation and induction programs are discussed.     

Teachers Describe Epistemologies of Science Instruction Through Q Methodology

Creating scientifically literate students is a common goal among educational stakeholders. An understanding of nature of science is an important component of scientific literacy in K‐12 science education. Q methodology was used to investigate the opinions of preservice and in‐service teachers on how they intend to teach or currently teach science. Q methodology is a measurement tool designed to capture personal beliefs. Participants included 40 preservice and in‐service elementary and secondary science teachers who sorted 40 self‐referential statements regarding science instruction. The results identified three epistemologies toward teaching science: A Changing World, My Beliefs, and Tried and True. Participants with the A Changing World epistemology believe evidence is reliable, scientific knowledge is generated in multiple ways, and science changes in light of new evidence. The My Beliefs epistemology reflects that scientific knowledge is subject to change due to embedded bias, science is affected by culture and religion, and evolution should not be taught in the classroom. The Tried and True epistemology views a scientific method as an exact method to prove science, believes experiments are crucial for scientific discoveries, absolute truth exists in scientific knowledge, and society and cultural factors can be eliminated from investigations. Implications for preservice teacher education programs and in‐service teacher professional development are addressed.     

The Effects of a Mathematics Infusion Curriculum on Middle School Student Mathematics Achievement

Increasing mathematical competencies of American students has been a focus for educators, researchers, and policy makers alike. One purported approach to increase student learning is through connecting mathematics and science curricula. Yet there is a lack of research examining the impact of making these connections. The Mathematics Infusion into Science Project, funded by the National Science Foundation, developed a middle school mathematics‐infused science curriculum. Twenty teachers utilized this curriculum with over 1,200 students. The current research evaluated the effects of this curriculum on students' mathematics learning and compared effects to students who did not receive the curriculum. Students who were taught the infusion curriculum showed a significant increase in mathematical content scores when compared with the control students.     

Reinventing the formal definition of limit: The case of Amy and Mike

Relatively little is known about how students come to reason coherently about the formal definition of limit. While some have conjectured how students might think about limits formally, there is insufficient empirical evidence of students making sense of the conventional ?-δ definition. This paper provides a detailed account of a teaching experiment designed to produce such empirical data. In a ten-week teaching experiment, two students, neither of whom had previously seen the conventional ?-δ definition of limit, reinvented a formal definition of limit capturing the intended meaning of the conventional definition. This paper focuses on the evolution of the students’ definition, and serves not only as an existence proof that students can reinvent a coherent definition of limit, but also as an illustration of how students might reason as they reinvent such a definition.     

北京大学“你好营养”健康宣教公益团队社会实践活动探索

北京大学“你好营养”健康宣教公益团队是由北医营养与食品卫生系33名研究生组成,在本院系专家教授的指导下,以公益讲座、网站宣传等形式为社区居民服务,通过健康理念传播提高公众营养和健康意识,实现“履行社会责任、知识回报社会”。2010年4月到8月,“你好营养”团队以城乡结合部社区居民为重点服务人群,在北京和太原两地完成12个社区共20场营养健康宣教和营养咨询服务系列活动,参与人数达3 500余人,多家媒体给予关注报道。团队正在实施和规划中的活动包括响应相关政策,在北京逐步建立多个“营养改善示范社区”,在全国医     

科学之美——科学与全民美学素质

美是一种自然、社会和艺术互相交融的范畴,在科学中发挥着神奇的作用。综观科学史,科学美发源于古希腊毕达哥拉斯学派的数学理性传统。科学之美表现了人类生存和发展、进步的过程,也体现了自然存在之美。科学美已经成为科学家们从事科学探索的强大动力,也成为了联结科学和人文的纽带。培养全民的美学素质既有助于大众养成良好的人生价值观,也有助于建设社会主义和谐社会。     

中国极地科普教育的探索与实践——结合国际极地年中国科普活动

极地世界以其特有的科学、环境、美学、荒野等价值强烈地吸引人类前往探险、考察和旅游。这为极地科普工作的开展创造了独特的机会。本文较系统地提出并首次分析我国极地科普的基本目标、特点与基本思路。从实施内容、组织方式和成效等多个视角来对比分析国际极地年期间我国开展的极地方面公众推广与科普活动,这些活动体现出时间跨度长、主题与内容突出、资源有效整合、国内外协作广泛、影响大、成效突出等特点。在总结其实践经验和成效的基础上,进而提出极地科普工作新的构想和建议。