崇仁1、组合图形的面积 - 光泽县崇仁新华中心小学-网站首页(1, the area of the combination of graphics - sheen County Chongren Xinhua Central Primary School - home page)

新华网站  时间:2021-04-26  阅读:()

1、组合图形的面积-光泽县崇仁新华中心小学-网站首页1, thearea of the combination of graphics - sheen County Chongren

Xinhua Central Primary School - home page

First, review the introduction, reveal the subject

1, review the last lesson, characteristics about thecombination of graphics, method for the combination of graphicsarea.

2. Reveal the content of this lesson and write the topic onblackboard.

Two. Guiding practice

1 and first questions

(1) the students' independent thinking, segmented learnedarbitrary graphics.

A, B, display the student independent segmentationsegmentation

(2) students will be divided into graphic please least learnedgraphics.

(3) add the condition for segmentation.

A, students according to the conditions of B, why do this?2 and second questions

(1) free reading problems, understand it.

(2) formulation calculation

A, ask for the area of the wall to be painted first

10 x 1.6 / 2 x 410

B, and then figure out how many kilos of paint it will take

0. 15 X 48 = 7.2 (kg)

When communicating, if the students make a comprehensiveformula to calculate, as long as reasonable, teachers shouldalso be affirmed.

3 and third questions

(1) read the question freely and discuss how to solve theproblem of "how much paint is needed. ".

(2) students practice

(3) reporting feedback.

Three. Exercise independently

(1) presentation exercises

1. narrative calculation thinking.

The students discuss with each other exchange.

2. for the upper icon on the data, the area.

Can the students finish after the exchange.

3. narrative calculation thinking.

S umm ary:

First, the combination graph is divided into several basicplane figures, and the area is calculated by the basic figurearea formula, and then the parts are added together.

(two) solving problems

There is a irregular, figure, if the area of

0.2 square meters of floor tiles, at least the number of tiles?Four. Summary of the whole lesson

Through this class of practice, what was your experience?Five, assignments: seventy-fifth pages of practical activities2, exploration activities - "footprints of growth"

Teaching contents: bjnu edition textbook of mathematics ninthpage 77-78 content.

Teaching objective:

1, knowledge and skills: can correctly estimate the size ofirregular graphics area, can use the number square method tocalculate the area of some irregular graphics, master the orderand method of the number grid.

2, the process and methods: by means of grid map estimation ofirregular graphics area, in the process of estimating the areaof experience to solve diversity strategy, develop preliminaryestimate consciousness and estimate the habit, experience thenecessity and importance of estimation.

3, emotion, attitude and values: understand the closerelationship between mathematics and real life, and feel theapplication value of mathematics.

Teaching emphasis: map estimation irregular figure area usinggrid.

Teaching difficulties: habits and the choice of estimationmethods.

Teaching thought:

In real life, the students will be exposed to the problem areaof a large number of irregular graphics, according to therequirements of the standard, let the students grasp theestimation of irregular graphics area, is one of the studentsthe concept of space, but also improve a student' s ability to

solve the actual problem. This class is the teachingmethod forstudents can master solving math problems and the.

Teaching preparation: a plurality of leaves, square piece ofpaper, a small blackboard says "do you know".

Teaching process:

A situation, guide, reveal new knowledge.

Today, the teacher brought two significant footprints. (thefirst footprints on the moon) . Maybe one day after several years,the first Chinese footprints on the moon are among the peoplepresent. Look at the second step: (show?Her footprints) thisis a millennium Baby Footprints pictures, how can we know howmuch this footprint area?

Two, participate in exploration, experience new knowledge1, his first independent estimates, then the exchange withinthe group.

2, the whole class exchange:

(1) explain the result and process of estimation

(2) the number square method is used to verify the estimatedvalue

(3) teacher: everyone is estimated by the method of the numberof squares,

Is there any other estimation method?

Guide the students to look at the graphics as approximategraphics, and calculate the area according to the area formulaof the graph

3, show the two Xiaohua footprints, students estimated area:Three, summary method, practice new knowledge:

(1) teacher: just nowyou estimate the area of irregular figuressuch as footprints. Think about what methods you used toestimate

Divisionwriting: 1. With the help of the grid map count number.2, take it as an approximation of the regular figure, aftermeasuring calculation.

(2) ask the students to count their footprints of the area isabout how much?

The students take their first independent step, and with thehelp of the attached 3 grid footprint area estimation.Four, new knowledge practice, solve the problem:

1, to estimate the irregular Seventy-eighth page graphics area:(in order to produce courseware)

(1) students estimate independently:

(2) on the exchange students talk about how to estimate the.

2. Estimate the area of the palm:

(1) : each value your palm area:

(2) estimate and verify the students cooperation on the gridpaper: (this link tohelppoor students to carry out activities)

(3) report shows: (Teacher: we know that square decimeter, palmarea is about 1 square decimeter)

Six, classroom review, summary and improve:

Boys and girls, what do you have today?What do you have? Tellme。

Blackboard writing design:

Footprints of growth

Estimation of irregular figure area:

1, with the grid count.

2, take it as an approximation of the regular figure, aftermeasuring calculation.

Second class: area of practice -- estimation of leaves

Teaching contents: bjnu edition textbook of mathematics ninthvolume seventy-ninth pages.

Teaching process:

(1) revealing the contents of activities

(two) activity process

1. Select leaves

2. Estimate the area of a leaf:

(1) Division: each group took out the leaves, first calculatethe area of each other. Can direct to find its size by numberof squares?

(2) students discuss, named answer:

(3) birth report: (a) count on the grid. (b) the outline drawnon the grid paper, count.

(4) with each other about the results, see who the most accurateestimate.

3, understand the importance of green trees to environmentalprotection:

(1) if a tree with 10000 leaves, the total area of the treeleaves all estimate.

(2) in sunny days, about 25 m2 of leaves can release enoughoxygen for one person to breathe in one day. The tree in thesun, a day to release oxygen to meet the needs of many peopleto breathe?

Note: (show, do you know?)

You know what?

A person to live, need every day in 0.8 kg of oxygen, 0.9kilograms of carbon dioxide discharge. The 10 thousand squaremeters of forest oxygen can supply one thousand peoplebreathing.

Data introduction:

10 square meters of forest or 25 square meters of grass canabsorb all the carbon dioxide exhaled by one person every dayand supply the needed oxygen. Globally speaking, green forestevery year for people of nearly one hundred billion tons ofcarbon dioxide, 60%oxygen for clean air. The existing forest,the annual production of up to 55 billion 500 million kg ofoxygen.

4, talk about the feelings of this lesson.

Try and guess

The first class: Chicken with rabbit cage

PIGYUN:美国联通CUVIPCUVIP限时cuvip、AS9929、GIA/韩国CN2机房限时六折

pigyun怎么样?PIGYunData成立于2019年,2021是PIGYun为用户提供稳定服务的第三年,目前商家提供香港CN2线路、韩国cn2线路、美西CUVIP-9929、GIA等线路优质VPS,基于KVM虚拟架构,商家采用魔方云平台,所有的配置都可以弹性选择,目前商家推出了七月优惠,韩国和美国所有线路都有相应的促销,六折至八折,性价比不错。点击进入:PIGYun官方网站地址PIGYUN优惠...

wordpress投资主题模版 白银黄金贵金属金融投资网站主题

wordpress投资主题模版是一套适合白银、黄金、贵金属投资网站主题模板,绿色大气金融投资类网站主题,专业高级自适应多设备企业CMS建站主题 完善的外贸企业建站功能模块 + 高效通用的后台自定义设置,简洁大气的网站风格设计 + 更利于SEO搜索优化和站点收录排名!点击进入:wordpress投资主题模版安装环境:运行环境:PHP 7.0+, MYSQL 5.6 ( 最低主机需求 )最新兼容:完美...

无忧云(25元/月),国内BGP高防云服务器 2核2G5M

无忧云官网无忧云怎么样 无忧云服务器好不好 无忧云值不值得购买 无忧云,无忧云是一家成立于2017年的老牌商家旗下的服务器销售品牌,现由深圳市云上无忧网络科技有限公司运营,是正规持证IDC/ISP/IRCS商家,主要销售国内、中国香港、国外服务器产品,线路有腾讯云国外线路、自营香港CN2线路等,都是中国大陆直连线路,非常适合免北岸建站业务需求和各种负载较高的项目,同时国内服务器也有多个BGP以及高...

新华网站为你推荐
支持ipadipad如何上网苹果ipad无线上网卡怎么设置?iphonewifi为什么我的苹果手机连不上wifi联通版iphone4s联通版iPhone4s 用联通3G卡好还是移动的好重庆电信宽带管家电信的宽带上网助手是什么?csshack针对IE6的CSS HACK是什么?firefoxflash插件Firefox浏览器怎么激活adobe flash插件routeadd如何用route add添加本地路由表,使一个网段的机器能访问另一个网段局域网的机器。望高手指点。chrome172017款领航员四驱长轴3.5T车身长宽高马力油耗多大17款领航员报价altools.u32keil中字符类型u32什么意思
directspace Dedicated 私人服务器 174.127.195.202 坐公交投2700元 91vps 国外代理服务器软件 酷番云 吉林铁通 东莞idc 外贸空间 美国凤凰城 主机管理系统 iki ledlamp 购买空间 空间申请 江苏徐州移动 国内空间 阿里云个人邮箱 更多