| 类型：原创 | 来源：化学与教学资源研究所 | 作者/推荐人：admin | 点击量：816839 | 时间：2011年6月14日 13:37:36 |
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研究所2011届硕士毕业论文摘要 ◎ 2011届硕士毕业生刘国英 题目：三层次四重表征教学模式下的高中化学学科关键词的教学研究——以高中化学原理概念“化学平衡”和“酸碱中和滴定”的教学为例 摘 要 “化学平衡”、“酸碱中和滴定”是化学学科中的核心概念，在中学化学学科的100个关键词中，“pH、化学平衡、中和反应”分别位列第10、25和33位，仅次于“物质的量、摩尔质量”等物质概念，是深刻理解化学学科内容的重要概念。这一类以图像曲线为载体的化学概念，涉及化学反应的本质原理，与曲线相结合的概念表征方式会大大提高这些化学概念的复杂性和抽象性。这一类化学原理概念是历年高考中的重点和难点，而高考中对于这些概念的考察，通常是以图像曲线的形式进行的，因此对学生的知识理解深度，从图像中获取信息的能力，以及概念与曲线的表征转换的水平都提出了更高的要求，是高中生化学学习的难点。 四重表征是化学学科的独特思维，化学学习中从宏观现象、微观粒子原理、符号方程式和曲线变化趋势四个水平共同理解同一化学问题，可以提高学生化学问题解决的能力。本研究与以往的研究不同，从多重表征角度思考化学问题，以加涅学习条件论为依托，首次建立一套有效的三层次四重表征教学模式。针对高中化学核心知识“酸碱中和滴定”、“化学平衡”等原理概念学习当中遇到的迷思，以四重表征教学模式为基础得出适合图像曲线为载体的概念教学设计方案，在高中进行不同课型的教学实施，以提高学生在学习相关概念以及处理以图像为载体的问题时的方法和能力,培养学生四重表征的化学学科思维。 本研究主要分为五个部分。 第一部分是第一章：绪论。对课题的研究背景、研究内容进行阐述，并提出研究的问题，对研究中涉及的概念进行相关界定。本文所探讨的问题是，学生在理解以曲线为载体的化学原理概念过程中，知识和思维上存在哪些困难？而借助于四重表征教学模式是否能有效地解决这些困难,并提高学生处理图像型化学问题的能力？ 第二部分是第二章：文献调研。在对国内外的文献进行综述的基础上，了解化学多重表征的发展现状和多重表征与课堂相结合的概况，同时了解国内化学原理概念的教学情况。对正式研究过程中的四重表征教学模式的构建以及原理概念的教学内容，教学方案的设计提供理论指导，并为研究案例的选择提供必要的参考。 第三部分是第三章：调查研究。分别以教师与学生为调查对象，以“化学平衡”“酸碱中和滴定”为调查内容，调查施教者和学习者的四重表征水平及能力，为第四部分的研究提供前期的实践指导。 调查研究1利用MAS(多维分析系统)编制问卷，调查一线化学教师在化学平衡知识中宏观、符号以及微观表征的水平以及表征转换之间的能力，从老师角度分析如何将多重表征思维方法有效应用到课堂当中。研究发现，化学一线教师在多重表征的水平以及转换能力上存在困难和问题，这些困难和问题会直接导致教师在化学课堂的教学当中教学手段表征的单一化，教师可以在备课和授课两个阶段贯穿多重表征思维，创造性地使用教材，以提高教学效果。 调查研究2采用CK（Chemical Knowledge text）和SMV:Chem(同步可视化模拟软件)调查高中学生在学习新知识时对四种表征（宏符微曲）应用的先后顺序、重要性以及表征结合情况，以从学生角度思考表征转换问题。研究发现，（1）高中学生对于问题解决过程中的四种表征是有侧重的，题目提供的信息表征为主要表征，符号方程式表征为主要的问题解决表征，而其他两种表征作为辅助表征，并能初步建立两种表征之间的联系。（2）而对于新知识，高中生趋向于首先利用宏观表征去了解这一知识，符号表征作为辅助理解表征，数据图表和曲线的变化用来理解宏观现象出现变化的原因。这为四重表征教学模式中的表征转换环节设计提供了学生层面的认知基础。 第四部分是第四章：模式建立。 以加涅的学习条件论和信息加工理论为理论指导，调查研究的结果作为参考，结合相关的文献建立三层次的四重表征教学模型，模型将教学过程分为三个层次，以此模型为基础建立以化学原理概念为教学内容的四重表征教学模式（Tetra-Representation Teaching Model，TRTM）。 第五部分是第五、六章：实践研究。将TRTM分别设计应用于高三的复习以及高二的实验课堂两个案例，利用不同的课型检验TRTM的教学效果。 实践研究1利用“化学平衡预测卷、前测卷A（CEIT A）”和出声访谈了解高三学生对于以图像为载体的化学平衡抽象概念理解的困难和迷思，针对这些困难和迷思结合四重表征模型设计四重表征教学策略和环节，利用互动反馈系统得到即时反馈结果，课后利用“化学平衡后测卷B（CEIT B）”进行实验班和控制班的前后测教学效果比较，以了解课堂教学效果、学生的概念理解和图像处理情况。研究发现：（1）高中学生在理解带有图像特征的抽象概念是存在迷思和困难的。这些迷思和困难包括两个层面：知识层面和图像层面；（2）TRTM教学模式在概念知识的系统性、获取图像信息的深广度，多重表征转化、图像分类观，知识的曲线问题表征能力、多变量图像处理方法本质的理解（对问题的举一反三）以及图像绘制的理解和方法上，高于传统的教学模式。但在知识点的巩固和强化上由于习题练习的缺乏而略差于传统的习题教学模式。 实践研究2利用手持技术直观表征酸碱中和滴定曲线，结合四重表征教学策略和POE（预测-观察-解释）策略，将TRTM应用于高二新知识的实验课中，以问卷测试和个别访谈调查被试对知识的理解情况以及对教学过程的看法，以更全面地了解TRTM教学模式的教学效果。研究发现：TRTM教学模式应用于不同类型的课堂具有相同的效果，对于同类的化学概念，改变TRTM教学模型的表征引入方法与不同阶段的表征转换方法，可以适用于不同的课型。 本文重新梳理了多重表征的内涵，首次建立了三层次的四重表征教学模式，针对高中生对于以曲线为载体的化学原理概念的知识和图像层面上的困难和迷思实现概念教学的有效性，从而实现学生思维和能力上的提升。一方面可以为化学一线教师在这一类化学概念的教学中提供一些参考，另一方面可以为表征理论的研究提供化学学科的教学案例，具有理论和应用的双重价值。 关键词：加涅学习条件论；四重表征教学模式；化学学科关键词；化学原理概念；化学平衡；酸碱中和滴定；图像理解 A RESEARCH ON KEYWORDS IN CHEMISTRY TEACHING BASED ON THREE-LEVELS TETRA-REPRESENTATION TEACHING MODEL(TRTM) IN HIGH SCHOOL "Chemical equilibrium "and "acid-base titration" are the core concepts in chemistry.“pH、Chemical equilibrium and Neutralization”are ranked No.10、No.25 and No Tetra-Representation is an unique thinking in chemistry, it can improve the chemical problem solving skills when the students understanding the chemical problems by four levels: Macro-micro-symbol-curve. This research was based on the learning conditions of Gagne, an effective multi-level TRTM was established for the first time. This model was aimed for the problem on these abstract principle concepts which were "Chemical reaction rates、chemical equilibrium "、 "acid-base titration, ".Any different instructional program were devised based on the TRTM and applied on the key high school in GuangZhou to test the effectiveness of teaching by TRTM. The first part is Introduction. The problem discussed in this paper is what are the difficulties in knowledge and thinking when the students understanding the chemistry principle concepts , and if these difficulties can solved effectively by TRTM? The second part is Literature Research. The researcher reviewed the domestic and foreign research progress of multiple representations and the situation of it used in the classroom, at the same time, this research finding out the situation of the chemistry concepts teaching in the research. The third part is Empirical Research. In Empirical Research 1, a questionnaire was devised by MAS (multi-dimensional analysis system) , investigated the chemistry teacher’s ability of “Marco-Micro-Symbol” representation and the conversion between them in the knowledge of "Chemical reaction rates、chemical equilibrium ",and then, study analyzed the case to know how to use the Multiple representations thinking model into the classroom effectively from the teacher point of view. It found that teachers had difficulties and problems at the level and conversion capability of multiple representations .The result of these difficulties and problems of the concepts representation will made the teachers teaching singled in classroom . In Empirical Research 2, it investigated the students how to use “Marco-Micro-Symbol-Curve” to learn the new knowledge, include the order、importance and combination of these for representations. During the investigation, CK（Chemical Knowledge text）and SMV:CHEM(Synchronized Multiple Visualizations of Chemistry)must be used. It found that in problem-solving process , is not as important as each of tetra-representation among the high school students .The major representation is the presentation of information with the subject, the major representation of problem solving is symbol. The fourth part is Modeling. The teaching model of multiple representations was constructed on the results of empirical and literature research, which was based on the Gagne’s learning conditions and information processing theory. The fifth part is Practice Research. In Practice Research 1, “Chemical Equilibrium Image Test A (CEIT A)” and interview was used to test high school students’ the misunderstanding of chemical equilibrium. The Tetra - Representation thinking strategies for these misunderstanding. In the classroom, feedback system and synchronized micro simulate of chemistry were used. “Chemical Equilibrium Image Test B (CEIT B)” was used to test the teaching effect between experimental and control class after class. It found that:(i) The high school students had misunderstanding on learning the chemical abstract concepts with curve, it including two parts: concepts knowledge and curve treatment. (ii) The study results showed that the teaching effect of experimental and control groups were different, TRTM teaching is better than traditional teaching model at aspects as follows: the systemic of conceptual knowledge、breadth and depth of image information obtained、multiple representations thinking 、graphics category 、curve representation of knowledge problem、multi-dimensional image processing and the ability of drawing shapes. But it is not better than TTM on deeply understanding of knowledge. In Practice Research 2, based on the TRTM and POE(Predict - observe - explain)strategies, the curve of "acid-base titration"was drew by the handheld technology, at last, test volume and interview were used to find out the students’ knowledge level and their views on the teaching process. It found that TRTM had the same effect on different types of classroom, when the introduction and conversion of representation is changed at different methods and stages , TRTM is suitable for different class stype. "Chemical reaction rates、chemical equilibrium "and "acid-base titration" as research are closely related with curve representation, the study summarized the concepts knowledge and curve treatment misunderstanding of chemical abstract concepts in high school students, achieve the effectiveness of teaching by TRTM, Through this search, it can improve students’ thinking and ability on problem solving not only limited to problem itself. On the one hand,this research hope to supply any reference to chemistry teachers on teaching these abstract concepts, on the other hand, It can provided some chemical teaching cases for the representation theory. Key Words:learning conditions of Gagne; tetra-representation teaching model;keywords in chemistry; chemistry principle concepts; chemical equilibrium; acid-base titration; image understanding | ||||