05玩水没白玩(平阳昆阳一小陈红娟 谢作长)

2005年浙江省中教师论文评比 学 段: 小 学 学 科: 数 学 学 校: 温州市平阳县昆阳镇第一小学 姓 名: 陈 红 娟 谢 作 长 题 目: “玩水”，没白玩 professional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Resident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, planting is completed, often with a 1-2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and management, to ensure the lawn landscape continues for a long time. Lawn maintenance management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growing season, according to the different periods of precipitation is extremely important and timely irrigation of different grass species. Can generally be divided into three periods: ? turned green before the rainy season. High temperatures during this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength and rainy periods during which Bush 2-4. ? largely ceased during the rainy season irrigation. Air humidity during this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. ? to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater, ——《升和毫升的认识》案例研制与剖析 案例前的思考 新课程理念下如何开展课堂教学,这是每一位教师必须思考和探索的。观察现阶段的小学数学课堂教学，不难发现传统教学的诸多不良惯性依然在很大程度上束缚着教师。往往是学习的过程枯燥繁琐，缺乏生动活泼的个性体验;往往是学习的方式单一、被动，缺少自主探索、合作学习等机会;也往往是强调结果的“给予”，忽视让学生体验数学知识的形成过程。这些都在很大程度上压抑着学生的主体性发展，导致了积极的“体验学习”的缺失。可以这么认为，如何彰显新课程理念下数学课堂教学的靓丽生命，关键在于教师如何引领学生进行积极有效的“体验学习”。从这个角度出发，我选择了《升和毫升的认识》为研究载体。 《升》从数学的逻辑系统来说，是借助于体积的意义而存在的，多年来，我们都是把它放在了体积和体积单位之后教学，教材一般编排在五、六年级。但是容量这种现象，它其实跟重量、人民币等一样，都普遍存在于客观生活当中。自然的有很多进入孩子的视野，进入孩子的生活，孩子们早已有了关于容量的感性认识。我们完全可以从生活经验出发，在孩子们的实践活动当中体验感受，来认识升与毫升，因此我尝试着把它提前到三年级来上。 《升》作为一节概念课，传统教法执教者很容易“让我轻轻地告诉你”，觉得让学生知道有这么两个单位及其单位之间的进率关系就“功德圆满”了。其实不然，它有着更本质更逼近生命需求的一面，即在幼小的大脑里稳固地建立起这两个容积单位的空间表象，形成一定的空间观念，而这些将依赖于一种生动活泼富有个性的体验学习。那么，我们要思考的方向，便是教师调整角色，选择何种题材以及通过何种方式让每一个孩子展开快乐有效的“体验学习”。 为此我定下了这样的教学目标: 1、经历想象、观察、估计、验证等数学学习活动～体验1毫升、1升的容积有多大～及毫升与升之间的进率关系～会进行简单的换算。 2、在观察、操作、估计、合作交流的过程中～提高与同伴的合作交流能力～获得成功体验～并感受学习数学的快乐～提高学习数学的兴趣。 es dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re2 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin?4. -erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention prop 3、体验数学与日常生活密切相关～自然感悟生命的教育。 es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re3owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an, tran turned green before the rainy season. High temperatures during this period? 第一次实践〃案例描述与反思 【案例描述】 教 学 过 程 生成与反思 内容与本课知识有关～欣赏动画片段:大头儿子感冒吃药与喝水，小头爸爸(一) 评课时算不算正课内容? 课前 介绍吃药与喝水的健康知识。 学生发现了容量之后～ 只说出符号～并没有解释这 个符号所代表的实际意义。1、学生介绍自己带的容器，观察是用什么做单位的, 教师应该再追问。 (二) 单位的运用仅局限于2、小结:各种饮料、水等液体一般是用升与毫升做单 学生所答。老师可收集饮料引入 位的。并引出课题。 之外的相关照片～让学生体 会到升与毫升在生活中的 广泛运用。 两杯水的对比～学生的出示半杯的澄汁、半杯牛奶。 表现不能吻合老师的预设～1、猜一猜:这两杯饮料，哪杯多些，哪杯少些, 出现零乱、反复的场面。比2、讨论:可用什么方法来验证, 如学生选择用同样的杯子学生汇报各种方法，教师评价，并进一步提出:想知(三, 很清楚地比出两杯水的高道两杯饮料相差多少怎么办呢,引出测量工具。 低时～他们给老师的回答就比较 3、介绍量杯、量筒，并指导看刻度线的方法。 是多那么多～然后用手势比4、验证:请两位学生分别用量杯、量筒上台演示。并划出来～而不能很自然地引引导学生观察水面在哪个刻度线上，结果得出澄汁比牛奶出量杯量筒以及毫升这个多10毫升。 容积单位。 操作上～学生用针筒吸1、建立毫升的观念 1毫升的水还需要教师的指?玩一玩1毫升的水 导～将筒内的水剂到手心a.猜:刚才两杯饮料相差10毫升，那请大家猜一猜1 窝～基本上没有学生操作到毫升水有多少, 位。 b.玩:用针筒(先介绍针筒的刻度线)吸1毫升的水，(四) 数一毫升有多少滴～目放在手心里玩一玩。 的是让学生从不同的角度探究 c.数:1毫升水会有多少滴, 建立亳升的空间观念～实际?玩一玩10毫升的水 上是在消解一毫升很少的用针筒吸10毫升的水，挤入杯中，玩一玩，与1毫升先前观念～觉得还有这么 多～所以可以去掉。 比一比，并讨论你又看到了什么,又有什么想法, ?玩一玩100毫升的水 largely ceased during the rainy season irrigation. Air humidity durin?4. -erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention propes dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re4 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l 玩10毫升时还是由老估计一下，100毫升的水大概在水杯的什么位置，然后 师手把手扶着～这里可放小组成员盛水，轮流倒入量杯量一量，看谁最接近100毫 手～体现方法多样化。 升。 2、建立升的观念 小组里每人都打一杯?玩一玩1升的水 水～显得有点零乱～而且每 a.小组合作把量杯里大约100毫升的水用针筒调整准人都只顾自己～合作不起确。 来。所以可改小组合作三个 b.猜:如果10个小组都把这100毫升的水倒在一起，人先估计100毫升的水有多就是多少毫升呢,讲台上几个空瓶哪个能盛得下, 少～再打一杯水～最后倒在 量杯里测量。看哪里组最c.验证:十位组长按顺序倒入一个空瓶中，结果显示这 准。最后用量筒。如果个空瓶刚好能盛1000毫升，提示:1000毫升有没有另外说 不准最后调整。 法,引出升。 ?玩一玩2升的水:(举起2升的空瓶)这空瓶可以盛 出示三个空瓶起干扰多少水, 作用～势必影响课堂的流畅 学生猜测，教师倒水验证，并显示标签证实。 度。可改成直接出示1升的 3、换算: 空瓶～问:现在要把你们的 2升,( )毫升 水倒在这个瓶子里～你们认 2升350毫,( )毫升 为可以倒几杯,推倒出1升 =1000毫升。 1、喝水 要求把你带来的饮料或矿泉水倒在消过毒的刻度杯 平时孩子们基本上是里，喝一口，看喝了几毫升，有什么感受，你想到了什么， 直接在饮料瓶里喝的～把饮说给旁边同学听。 料倒在刻度杯里喝显然不小结:饮料含有色素，含有糖等对身体不利的东西，符合生活常态～同样学生喝水是人体所必需的营养素，对身体帮助很大，所以我们要的也不尽兴 少喝饮料，多喝水，要保证健康，一天我们小朋友要喝多 (五) 少水,(1升)像这样能放200毫升的一次性杯要喝上几杯 巩固 呢,(5杯) 对，为了我们生命健康成长，让我们大家一起每天坚 不能让故事情节或德持喝上五杯水吧～ 育的渗透冲淡数学味～同样2、大头儿子与小头爸爸动画题目: 也不能让形式上的热闹和?玩翘翘板:8升,( )毫升 9000毫升,( )升 精致喧宾守主。 ?有升800毫升，共有多少毫升 每次献务200毫升，( )人献血，共多少毫升, largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an, tran turned green before the rainy season. High temperatures during this period?es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re5owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. 【微格反思】 第一次实践过后，我欣喜地看到三年级的学生已有了比较丰富的相关知识储备，而且学习方式开放之后，学生也并没出现难以把持的大问题。但毕竟是一堂十分开放的课，每个环节都出现了许多值得反思的现象，我一边对各种生成现象作细微反思(上表“生成与反思”)，一边坚持批判与建议的原则，就一部分突出问题展开讨论，深入研究，寻求对策。 问题之一 教材中展现两杯水的比较目的十分明确，然而课堂中学生的思路却很难走上教材的“轨道”上来。 片段描述 师:两杯澄汁和牛奶。哪杯多一些,大家猜猜看。 ,学生信口回答～多一些、少一些或一样多三种情况 都有～场面一时有争执现象, 师:到底哪杯多一些～有什么办法,小组讨论一下。 生:放在同样大的杯子里～看两个是不是一样的。 生:把两杯饮料分别倒进一个杯子里～做记号～再比 高低。 生:用针筒抽～看分别能抽多少筒。 …… 师:你们这些方法可以知道多多少吗, 生:用多的减少的～大概多这么多。,学生用手势比划 多的部分, 师:要准确知道数量我们要请专门的工具来帮忙。 ,通过课件认识各种各样的量杯量筒, 师:比一比多多少。请两位同学上来操作。 生:澄汁是79～牛奶是63～ 师:多几, 生:16毫升。 批判?建议 陈洪清(教研员):两杯水的对比，学生表现不能吻合老师的预设，也就会有零乱，出现反复。比如学生选择用同样的杯子很清楚地比出两杯水的高低时，他们给老师的回答就是多那么多，然后用手势比划出来，而不能自然而然地引出毫升这个容积单位。 4. -erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention propes dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re6 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin? 周云书(师训员):同样，在这个环节预设学习容积单位的必要，难免会与第一个环节重复，也就是说在已经知道这两个单位的前提下，再来学习，不像长度单位或面积单位那样直接。如果想体现这样一种需要，则要将环节提到最前，但又不是最初的，因为课前谈话已经有提及。所以就不要预设。 执教者:但两杯水的比较又是教材的主体思路，同时能体现一些学习的乐趣与思维，应该要用。所以我们的定位就要变为引出一种工具的需要，而不能是单位的需要了。这样的操作只要求学生“你有什么办法比较出多少。”学生方法多样，在众多策略之中，引出量筒量杯的优越性。这是一种。 吴永远(听课者):另外，可以直接出示一杯水，让学生估计多少，然后引出量筒量杯，这也不失为一种简洁有效的方案。 问题之二 本课知识点比较简单，所以课堂波澜不惊。如何拓展课堂让学生感受更多，体验更充分。 片段描述 课后我们访谈了一部分学生～了解这节课的掌握情况及学习感受。他们一致地认为这一节数学课很有意思～但大部分学生认为知识比较简单～没什么挑战性。 批判?建议 吴恢銮(听课者):照理说五、六年级的课放在三年级上到这样的层次已经不易，但整节给我们的总体感觉还是比较“平”，学生的状态同样告诉我们，他们“吃不饱”，还能“消化”更多。这就迫使我们再深入地思考，在知识层面不能拔高要求的前提下，怎样在空间观念的建立等方面拓展有效的课堂空间。 钟振环(教研员):我觉得在课的最后阶段，很有必要进一步拓展，提高思维层次。比如将喝水与估计意识、估计能力的培养结合起来。老师请学生尽情地喝水，想喝多少就多少，然后让学生说说自己大概喝了多少毫升，这样对学生的能力发展就有了一种提升。 再度实践〃案例描述与点评 综合同伴和专家的意见，我又修改了原有的方案，集大家的智慧扬长避短，优化方案。如此反复，我又经历了两次的实践磨砺以及一次的全国教学大赛课。 【第二次实践】 这次上课基本上弥补了上次的不足，但我原先预想的“拓展”——让学生运用今天所学的知识估计喝水学问，却事与愿违。学生“吃喝玩乐”过火的担忧出现了，他们的估计毫无头绪，可以说是瞎猜。分析原因:一是教师没有强调整瓶水的原来重量，这就无从比较。二是三年级的学生思维水平还完全达不到从整体到部分的层次，所以无意中拔高了要求。三是学生自己所带的饮料没有一个统一的，各式各样的都有，这就造成了混乱。 , tran turned green before the rainy season. High temperatures during this period?es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re7owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an 【第三次实践】 一方面，在“喝水”这个环节上，有了很大的改进。首先要求学生带着问题去喝水，边喝边看，大概喝了多少。其次在喝好 之后小组交流，老师参与学生的估计活动，进行适当 的指导。另外在汇报阶段可以选择简单的估计，比如 半瓶水作为起始。另一方面，确定了本节课一明一暗 两条主线都能在孩子们身上得到较好的体现:明线— —孩子们通过各种活动充分感受1毫升、1升容积有多少，在大脑里建立起了1升、1毫升的视觉表象;暗线——孩子们在玩玩水、喝喝饮料、看看动画片中感受 到了学习数学的快乐，并自然感悟要多喝点水、少喝 饮料、按量吃药、输血救人等等的生命教育。 【第四次实践】 全国小学青年教师个性课堂教学大赛观摩评比活动于2005年4月30日—5月3日在河南郑州举行。来自北京、天津、吉林、广东、广西、上海、浙江、江苏、安徽、四川、内蒙古、河南等国家级课程改革试验区的优秀青年教师代表参与个性课堂教学评比， 作为浙江省代表执教《升和毫升》，全国各地近1500名教师观看了这次教学大赛和观摩活动。我 荣获一等奖第一名。互动点评时不仅获得与会教师一致认同和激情参与，也博得了李嘉骏、张梅玲、吴正宪、张兴华等国内知名专家较高的赞誉。 课堂回放 ,课前谈话及欣赏动画视频略, 一、引入 1、介绍: 师:同学们～今天我们一起来探究升和毫升的知识～你带的饮料跟升与毫升有关吗, 生1:我带的这瓶冰红茶有600毫升。,迫不及待地念出, 生2:我带的这瓶雪碧有550毫升。 生3:我带的这瓶矿泉水有596毫升。 师,惊讶地问,:毫升在哪里,你上来指给大家看看。(实物投影仪显示) 生:在净含量后面～ml就是毫升。 师:就是说毫升用字母符号ml来表示,板书毫升ml, 师:这596毫升什么意思, 生:就是这个瓶子净含量596毫升～有596毫升水。 师:老师也带来了一瓶饮料～我们看有多少,,实物投影显示2L, 生:2升。 es dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re8 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin?4. -erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention prop 师:升在哪里, 生:L就是升。 师:就是说升用字母符号L来表示。,板书升L, 2、举例: 师:同学们～除了各种饮料的多少需要用升与毫升作单位～生活当中还有什么东西的多少也需要用升和毫升作单位, 生:沐浴露、金龙油、咳嗽糖浆…… 师:老师这里也找到一些～请看,课件显示:啤酒、洗手液、袋装米醋、汽油等,～这些东西的多少一般需要用升和毫升作单位。 二、探究 1、建立毫升的空间观念 ?估计-验证 师,出示小半杯水,:请你估计一下这杯水有多少毫升, 生:100毫升、20毫升…… 师:这杯水究竟有多少毫升～你们有办法知道吗, 生1:用尺子量。,怎么量,,……,量出来是几毫升吗,,是几厘米～,这样的办法行不行以后我们再研究。, 生2:用针筒吸～再把它们加起来。 生3,兴奋地举起桌子上的量杯,:把它倒在这个有毫升刻度的杯子里～看一看不就知道了。 ,教师介绍量杯量筒～学生操作验证～测量出这杯水是58毫升, ?指导学生玩1毫升的水 师,举起杯,:同学们～58毫升是这么多～那1毫升的水有多少呢,请大家想象一下。 生1:很少很少只有一丁点。 生2:只有一滴水那么多。 生3:有一只蚂蚁那么多。 师:他的描述更加形象。1毫升到底有多少～我们一起用针筒来玩一玩。,指导学生看针筒上10毫升、1毫升的刻度, 师:大家吸1毫升的水～看看1毫升的水在你针筒里有多少,,学生吸水, 师,右手作手凹状,:吸好了～你可以把它挤到手凹里。小心不要让它跑掉了。,学生挤水, 师:下面请大家闭起眼睛～把这1毫升水记在脑子里。记住了吗,记住了～再睁开眼睛。现在谁来说说1毫升水有多少, 生1:在手掌心里只有一点点。 生2,举起无名指,:像无名指指甲盖那么大。 师:就那一片薄薄的指甲盖吗, , tran turned green before the rainy season. High temperatures during this period?es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re9owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an 生:包含着整块手指头。 师:这个比方打得真不错。 生3:1毫升水有三只蚂蚁那么多。 师:这位同学联想起刚开始认为1毫升只有一只蚂蚁那么多～现在经过玩水就比较准确地感觉到1毫升有3只蚂蚁那么多。这是一种多好的学习方法呀: ?学生自主玩10毫升的水 师:同学们～1毫升只有这么一点～那10毫升有多少呢, 生1:10毫升比1毫升多多了。 生2:有10个1毫升。 生3,举起针筒比划,:有这么多。 …… 师:那你去想办法取一个10毫升的水玩一玩。 ,学生讨论～选择方法～动手操作, 师:看到这10毫升的水你有什么想说的, 生1:1毫升水放在手心里放得住～10毫升放不住～会跑掉的。 生2,举起针筒,:10毫升水差不多有这么一针筒。,师:满满1针筒吗,,不是～是到刻度10这里。 生3,举起杯子,:10毫升水有一杯底。 师,示意这两位学生到台前来～并分别举起针筒与杯子,: 大家看到这～有什么想说的, 生:大的物体装10毫升～看起来比较少,小的物体装10毫升～看起来比较多。 师:什么意思你们听明白了吗, 生:10毫升在杯子里看起来非常少～在针管里看起来非常多。 师:这是怎么回事, 生:因为杯子的底面大～针筒底面小～所以在杯子里看起来这么少～在针管里看起来这么多。 师:看来10毫升放在底面大的容器里～看过去会矮一点,放在底面小的容器里～就显得高一些。实际上这里面都是多少毫升的水,,10毫升, ?小组合作玩100毫升的水 师,指着放10毫升的水杯,:假如把10毫升、10毫升倒在一块～100毫升有多少 生1估:有大半杯。 生2估:有小半杯。 …… 师: 100毫升究竟有多少你们还想玩吗,现在玩的要求更高了～先不准使用测量工具～以小组为单位～商量商量100毫升水大约到这杯子的什么位置,,小组商量?汇报, -erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention propes dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re10 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin?4. 师:大家就用这杯子去取100毫升的水。,学生打水, 师:我们要比一比哪一组眼力最准了～请各组把水倒入量杯里量一量。,小组合作测量, 师:我们统计一下～比100多的多的小组请举手,2组,～比100少的少的请举手,1组,～ 你们都很诚实。跟100差不多的请举手,7组,～你们真能干: 3、建立升的空间观念 ?全班合作玩1升的水 师:大家再来看一看～量杯里的水恰好是100毫升吗,如果不是～请小组合作把它调准 确。,各组纷纷用针筒调水, 师,出示净含量为1升的空瓶,:如果把10个小组量杯里的水都倒到这个空瓶里～你们估 一估会怎么样, 生1:刚好倒得下。 生2:可能会多一点点。 师:看来大家意见比较统一～那估得一定对吗, 生:倒一倒验证一下吧。 ,师生合作倒水～学生一边念几毫升一边看水在瓶里的位置～瓶子刚好能装1000毫升。, 师:同学们～现在这个瓶子里装有多少水, 生1:1000毫升。 生2:1升。 师:这是怎么回事, 生2:因为1000毫升=1升 师:原来你们早就知道～1000毫升还有一个名字叫…,1升, 师:那就是说1升等于什么,,1000毫升。板书:1升=1000毫升, 师,端起瓶子,:1升水有这么多～请大家闭起眼睛～把这1升水有多少记在脑子里。记住 了吗,记住了～就睁开眼睛。 师:平常你在哪里见过也像一升水这么多的东西, 生:我在超市里见过大瓶芬达大概有1升。 生,边说边比划,:我家用的金龙油跟这差不多。 生:烧杯刚好是1升的。 师:还有那么多同学想说呀,看来大家生活经验很丰富～下课再交流好吗, ?估计验证空瓶能装多少水 师,举起4升的空瓶,:这空瓶大概可以盛多少水, 生:3升、5升、4升…… 师:各有不同～重新倒水太麻烦～怎么办, 生:看标签。,4L, spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an, tran turned green before the rainy season. High temperatures during this period?es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re11owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2 师:谁估对了,你们估的真准:,板书4升, 4、换算: 4升,, ,毫升 5升350毫升,, ,毫升 三、应用 1、帮大头儿子与小头爸爸解决问题:,动画显示, ?玩跷跷板,选对了大头儿子就可以摘到苹果～选错了大头儿子会从跷跷板上摔下来。, 9000 毫升 ,, , 升 ,9 90, 一个开水瓶能装水3,毫升、升, 6升80毫升,, ,毫升,6800 6080, 一 瓶 眼 药 水 5 ,毫升、升, ?献血 A、一般成年人～体内一般约有4升800毫升血～是多少毫升, 师:同学们～医学专家告诉我们～献血不仅仅是献爱心帮助别人～而且能提高自身的造血功能～你回去也会劝你老爸去献血吗,会的请举手,师生统计,。 B、如果每位老爸都献血200毫升～这,27,个老爸一共能献多少血, 2、解决喝水,饮料,中的数学问题 ?喝水,饮料, 师:玩到这～大家有点口渴了吧～今天大家都带来了自己喜欢喝的矿泉水或饮料～要不要喝两口,别慌有个要求～先看一下你这瓶饮料有多少毫升,喝了再估一估你喝了多少,明白了吗,那就喝吧:,孩子们开心地喝喝、看看、比比、辩辩, ?估计并交流自己喝了多少毫升。 师:解渴了吗,请大家估一估刚才喝了多少～并说说是怎么估的, 生,边比划边说,:我大概喝50毫升。10毫升大概这么一点点～这里有五个这么一点点～大概就是50毫升。 生,边比划边说,:我觉得我喝了300毫升。原来没喝之前～水在这里～现在我喝完以后水到这里～喝掉的跟剩下的差不多～我的水是600毫升～600毫升减去它的一半就是300毫升。 …… 师:看来大家不仅仅会喝～也知道自己喝了多少。 ?回家估计并验证1升的水用自己平常喝的杯子要喝几杯。 师:刚才看了一下～大部分同学带的是饮料～同学们～饮料虽然好喝但有的含有色素、激素～对身体不利,水是人体所必需的营养素～所以我们要少喝饮料多喝水。要保证健康～我们小朋友一天大概要喝多少水,,1升, 师:同学们～如果用你们家里经常喝水的杯子一天大约要喝几杯呢,大家回去估一估～再想办法验证一下～好吗, 四、课堂总结 师:升与毫升给你留下什么感觉,你还有什么遗憾, erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention propes dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re12 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin?4. - 互动点评 执教者:最近我一直沉醉在升与毫升的世界里，非常快乐～记得我在构思这堂课时，几位同事共进午餐，席间，我们想要2瓶啤酒(每瓶500毫升)，我灵机一动朝服务员喊:“服务生，啤酒，来1000毫升～”服务员听的是目瞪口呆.当啤酒倒在杯里，大家也是猜得非常离谱。大人如此，何况小孩～ 这坚定了我对这堂课的定位。当然孩子不是没有起点，不说别的就说喝的，商店里以升或毫升作单位的各种饮料应有尽有，孩子们随处可见。我们要尊重孩子的生活经验，同时也要明白大部分孩子对升和毫升还只停留在知道的层面上。 这一课中，我预设了一明一暗两条主线，让孩子们通过各种活动充分感受1毫升、1升容积有多少，在大脑中建立起1升、1毫升的视觉表象作为明线，那么暗线则是让孩子们在玩玩水、喝喝饮料、看看动画片中感受到学习数学的快乐，并自然感悟到要多喝点水、少喝饮料、按量吃药、输血救人等的生命教育。 在多年教学生涯中，我发现课堂能激发孩子学习兴趣的，非常管用的一招就是——吃喝玩乐。有的玩、有的喝，当然是一件快乐的事，而升与毫升就在孩子玩玩水喝喝饮料中建立起了空间观念，升与毫升就在吃喝玩乐中进入孩子们的知识世界，满足了孩子内在的学习需要。 最后，我向在座的各位专家及老师们提一个倡议:让我们以爱心的名义，为了他人的生命，在您认为适当的时候，献出200毫升～为了您的健康，每天喝足1升600毫升，请记住:是水，不是酒～ 张梅玲(中科院心理研究所研究员、博士生导师):我第一次听到，上课怎么让孩子高兴 ——让孩子在课堂上吃喝玩乐，非常新鲜。对于“吃喝玩乐” 不要用我们平时的那种(比如吃，就是吃块面包什么的)来理 解课堂中的。我把这理解成我们老师的爱，老师的情，应该是 满足我们孩子最需要的东西。孩子最需要什么我们满足他，他 需要展示，我们给他展示;他需要成功，我们给他表扬;他需 要你的帮助，那么伸出你的真诚的大手拉起我们可爱的小手。就是说这种“吃喝玩乐”我认为把它理解成儿童的需要。另外，这节课体验得比较细致。从1毫升、10毫升，慢慢到1000毫升，逐步地体验，谢老师设计步骤比较细，那么在细的过程中孩子们体验也就比较细了。 张兴华(著名特级教师):《升与毫升的认识》主要是为了让 学生获得升与毫升的视觉表象、空间观念，在这一方面，谢老师 做了很有效的工作。他首先是从学生的生活经验出发，让学生玩 玩水、喝喝饮料。玩水是小朋友最喜欢的，所以对他们很亲切， 兴趣就一下子上来了，但玩水也不是瞎玩。首先让学生吸1毫升 largely ceased during the rainy season irrigation. Air humidity during this period, grass ?4. -d rainy periods during which Bush 2spiration, water requirements, and is one of the most crucial irrigation under soil water retention properties of strength an, tran turned green before the rainy season. High temperatures during this period?es. Can generally be divided into three periods: on, according to the different periods of precipitation is extremely important and timely irrigation of different grass specig seasmplemented according to a fixed pattern, following a number of technical points for reference. (1) the irrigation time growinronment is in a State of flux, coordination of water and soil and improving the microclimate of the Center, water cannot be ie enviproved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growth season, lawn and thng: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility environments can be immanagement, to ensure the lawn landscape continues for a long time. Lawn maintenance management includi 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-completed, often with a 1 ing issident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maintenance, plantprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re13owing of the leaf after this period before the rainy season precipitation, evaporation is greater, to yell?transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of lawn growth. 的水到针管里去，然后看一看，1毫升水有多少，然后再把1毫升的水让学生挤在手凹里，手凹里1毫升的水有多少呀,看清楚了吗,看清楚了，把眼睛闭上，在脑子里想一想，1毫升水有多少。在这快乐的一吸、一看、一倒、一看、一闭、一想的过程当中，学生对1毫升的空间意义就有了很深刻的印象，在脑子里就有了一个标准。所以，整个对升和毫升意义的建立，都是在学生实践活动当中感知，然后再建立表象形成的。皮亚杰说:“在动作性的活动当中对学生理解空间观念起到无比巨大的作用。”后面10毫升、100毫升也是在学生的实践活动中建立起这个表象，这是这节课上得很成功的地方。 河南省教研员:课程标准提出了课堂教学要从学生生活 经验出发，谢老师这节课把这个观点又深化一步，在课堂上 让学生增加生活经验，不仅从生活经验出发，而是增加了他 生活经验。 李嘉俊(中央教科所研究员):谢老师这堂课很成功，他抓 住一个我们当前核心的问题，我们要教什么,讲什么和怎么讲, 核心的问题要把我们学生热爱学习的这种意识，乐于学习的这种 意识，把它激发出来。他遵循了这一条，抓住了本质的东西，所 以这堂课上得这么轻松，效果这么好。 吴正宪(北京市教育科学研究院小学研究室主任):今天 这节课，给我留下了深刻而美好的印象。我最深的体会，就 是刚才张老师讲的——体验。如何建立这个空间观念，今天 谢老师的课这种学习方式与掌握基础知识之间不是矛盾的， 而是一个和谐的统一。他通过一系列的数学活动，学生在活 动中体验感受，建立了1毫升、1升的概念，我觉得这样非 常好。这节课，就如何来建立空间观念，给我们提供了很好 的空间。 执教者:就《升与毫升》这节课看，对“为什么体验”、“体验什么”及“怎样体验”有了较有成效的探索，但其他性质的课，能否在体验方面也能做到深透到位，也是说能否尽情的“吃喝玩乐”，有待于在今后教学中认真实践，并敬请各位专家、老师们给予指导。 erties of strength and rainy periods during which Bush 2ing this period, transpiration, water requirements, and is one of the most crucial irrigation under soil water retention propes dur turned green before the rainy season. High temperatur?different grass species. Can generally be divided into three periods: ion time growing season, according to the different periods of precipitation is extremely important and timely irrigation of rrigater, water cannot be implemented according to a fixed pattern, following a number of technical points for reference. (1) the ion, lawn and the environment is in a State of flux, coordination of water and soil and improving the microclimate of the Centh seasnvironments can be improved, adding water plant the lawn, is a guarantee of normal lawn. In view of the lawn during the growtce management including: irrigation, fertilization, pruning, weeding and other links. 1, irrigate irrigation lawn fertility emanagement, to ensure the lawn landscape continues for a long time. Lawn maintenan 2 lawn maintenance can grow into the fullness of the week. After the lawn grow, but also to carry out regular maintenance and-ntenance, planting is completed, often with a 1sident Engineer of the conservation section chiefs and marketing grasp work and coordination. Six and lawn maiprofessional engineer 1, each equipped with the professional technician 1, 2 technicians, carry out their duties. By the Re14 to yellowing of the leaf after this period before the rainy season precipitation, evaporation is greater,?awn growth. g this period, grass transpiration decreased soil moisture content has increased to a level sufficient to meet the needs of l largely ceased during the rainy season irrigation. Air humidity durin?4. -