人教版小學(xué)數(shù)學(xué)四年級(jí)《三角形的分類》教學(xué)設(shè)計(jì)

1、rapid development of the market economy environment to expl ore public servants 'duty c onsumption monetization reform hasprovided a good foundation. Thesocialization of rear service workhas been launched, and rapid progress in some places and departments, duty consumption monetization of carrie

2、r and a pproach to management has bee n resolve d. Third, in re cent years, exploring the monetization of duty consumption has made some progress, have gained some experience and can provi de reference to thecompre he nsive reform of the system of public serva nts ' dutyconsumption further. Impl

3、ementing an "honest canteen", standar dize official entertaining management; enhancing the telecommunication expe nse management; elimination of County travel andcountryside subsidies; research "village officials" capitalization ma nagement of corporate spendi ng, and so on. Fina

4、lly, group .18 session to be held inBeijing from Novem ber 9, 2013 to12th. 35 years ago ble w the t hird plenary sessi onof the reform and opening up in the spring breeze,changed, affect the world; t oday, 35 yearslater, in the eye s of thenation and the worldexpect , again to reform mark China, ush

5、ered in the 18 sessi on. XIGeneral Se cretary pointed out that China's reform has e ntered acrucialperiod and the Sham Shui PoDistrict, must be base d on greater politicalcourage and wisdom, l ose no time in deepe ning reform in important fields. Dares to cra ck a hard nut, dares to question the

6、 Rapids, w hich dares to break the barrier of ideas, anddare tobenefitcure barriers.Deepening reform andopeni ng up is on schedule to achieve i nstitutional safeguards of the moderately well-off. Under the "five inone" the Ge neral layout of socialist modernization requirements, 18 session

7、of the decision wasa "five in one" and the impr ovement of overall scheme of reform, will prom ote an integrated and coordinatedeconomic,reforms and the party'sconstructionin the area of institutional reform.The "five in one" programme is to achieve acomprehe nsive reform of

8、institutional guarantees forobje ctives ofbuild a well -off society, the smoothprogress of theconstruction of a well-off society and reform the objectives of theprogramme.One, holding time and place importance on November 9,2013 t o the 18 session of the 12thBeiji ng since 1978, 35,have been 7 plena

9、ry session, each time on major issues of political andeconomi c life of thecountry has made important deployment. In accordancewith PRC political practice,often at every session of theCPC Ce ntral Committee ina plenary session washeld immediately after the party'sCongress,on the theme "pers

10、onnel",discussing election Central's top leaders, such as the election of the StandingCommittee of thepolitical Bureau, through the Central Committee members, decisions, such as members of theCentral Military Commission.The second plenary session, ishel d in two sessions before the general

11、election, mainly todiscuss anew State personnel issues. But by the third三角形的分類教學(xué)設(shè)計(jì)教材內(nèi)容 本課的教學(xué)內(nèi)容是人教版課標(biāo)實(shí)驗(yàn)教材四年級(jí)下冊(cè)“三角形”單元例4教學(xué)目標(biāo) 1、使學(xué)生認(rèn)識(shí)銳角三角形、直角三角形、鈍角三角形和等腰三角形、等邊三角形，知道這些三角形的特點(diǎn)并能夠辨認(rèn)和區(qū)別它們。2、經(jīng)歷分類的過程，滲透分類的數(shù)學(xué)思想，培養(yǎng)學(xué)生的空間觀念和初步的邏輯思維能力。3、在共同學(xué)習(xí)中，訓(xùn)練學(xué)生的自我探索能力，在探索活動(dòng)中培養(yǎng)學(xué)生主動(dòng)探索精神和創(chuàng)新意識(shí)。教學(xué)重、難點(diǎn) 教學(xué)重點(diǎn)：認(rèn)識(shí)銳角三角形、直角三角形、鈍角三角形以及等腰三

12、角形、等邊三角形的基本特征。教學(xué)難點(diǎn)：發(fā)現(xiàn)三角形的角、邊特征從而正確分類。教學(xué)過程 一、情境引入1、復(fù)習(xí)銳角、直角、鈍角的大小關(guān)系。同學(xué)們還記得它們嗎，誰來說說它們之間的大小關(guān)系？2、師：今天老師給同學(xué)們帶來了6 個(gè)小朋友，你們都認(rèn)識(shí)它們嗎？（課件出示）（ 1）是的。（點(diǎn)擊課件）前面我們已經(jīng)學(xué)習(xí)了三角形，誰來說說三角形有幾條邊，幾個(gè)角，幾個(gè)頂點(diǎn)？（ 2）這些三角形的形狀相同嗎？那我們來看看這些形態(tài)各異的三角形有什么煩惱？ （點(diǎn)擊課件）（ 3）同學(xué)們能幫上它們的忙嗎？二、合作探索1、按角分類（ 1）那好吧，我們先按角來分類。你能知道這個(gè)角是什么角嗎，你用什么方法判斷？還可以用什么方法？哪種方法最

13、快？（ 2）這個(gè)角有點(diǎn)像直角，又有點(diǎn)像鈍角，分不清，怎么辦？（用三角尺的直角去測(cè)量）（ 3）小組合作，按角分類，完成研究表 1。編號(hào)三角形銳角直角鈍角plenary session, each sessionof the Ce ntral Committee of national institutions and personnel problems have been arranged, you ca n concentrate on nationaldevelopment and reforms.Previous plenary session is often branded with

14、 a central leading collective,often by looki ng at the third plenum of the initiative to found thecurrent central leadershipcollective gover nance characteristics.From the analysis of theprocess of e conomic reform in Chi na, plenary session,12 session, 14,16 ple nary se ssion haveprogrammatic meani

15、ng, respectively, marking the four stagesof China 's economic reform, and that the start-upphase of reform, reform, constructionphase and perfe cting the Sociali st market economy framework stage of socialist market economy.Previous plenary session topicspropose d to the thirdplenarysessi onof &

16、quot;taking class struggle as the key link," shifted to socialist modernization;12 session marked the change from rural tourba n, established with publicow nership as the Foundatiwhenbot h the old and thenewsystem change , governance a nd rectify the economic order; 14 . Fair and efficient and

17、a uthoritative Socialist judicial system,safeguard thepeople's interests.Legal authority to uphold theConstitution,dee pening the reform of administrative law enforcement, ensure that the right to exercise judicial power i ndepe ndently and impartiallyaccording tolaw theprosecution,perfecting th

18、e running me cha nism of judicial powe r, improve thesystem of judicial protectionof human rights. Plenary sessi on, Affairs the right to adhere to t he system, and l et the people authority to let thepower run in the S un, isshut up in acage of the systempower policy. Decisi on S cie nce, implement

19、ation shoul d beconstructedstrong, supervi se the ru nning of powerfulsystem, improvethe sy stem of punishingand preventing corruption,promotiinstitutional innovati on and institutional protecti on, sound improvement stylenormal system.Plenarysessi on, building a socialist culture in China, enha nci

20、 ng nati onalcult ural soft power, must adhere to the orientationof advanced Socialistculture , adhere to the developmentof Sociali st culturewith Chi nese chara cteristics, a dhere to t he peopl e-centred work-oriented, furtherdee pening reform of culture.To improve the cultural management system,

21、establish and improve the modern market system and building modern publi c cultural service system, improve the levelof culture openi ng. Plenary session, a chieving development results moreequitablebenefit of all people, we mustspeed up reform of social programs and solve the issues of concern to t

22、he pe opl e the mostdirect and real interest, and better meet theneeds of the people.o deepen education reform, improve institutional mechanisms for therapid development of the market economy environment to explore publi c servants 'duty consumption monetization reform hasprovided a good foundat

23、ion. Thesocialization of rear service workhas been launched, and rapid progress in some places and departments, duty consumption monetization of carrier and a pproach to management has bee n resolve d. Third, in re cent years, exploring the monetization of duty consumption has made some progress, ha

24、ve gained some experience and can provi de reference to thecompre hensive reform of the system of public serva nts ' dutyconsumption further. Implementing an "honest canteen", standar dize official entertaining management; enhancing the telecommunication expe nse management; eliminatio

25、n of County travel andcountryside subsidies; research "village officials" capitalization ma nagement of corporate spendi ng, and so on. Finally, group .18 session to be held inBeijing from Novem ber 9, 2013 to12th. 35 years ago ble w the t hird plenary sessi onof the reform and opening up

26、in the spring breeze,changed, affect the world; t oday, 35 yearslater, in the eyes of thenation and the worldexpect , again to reform mark China, ushered in the 18 sessi on. XIGeneral Se cretary pointed out that China's reform has e ntered acrucialperiod and the Sham Shui PoDistrict, must be bas

27、e d on greater politicalcourage and wisdom, l ose no time in deepe ning reform in important fields. Dares to cra ck a hard nut, dares to question the Rapids, w hich dares to break the barrier of ideas, anddare tobenefitcure barriers.Deepening reform andopeni ng up is on schedule to achieve i nstitut

28、ional safeguards of the moderately well-off. Under the "five inone" the Ge neral layout of socialist modernization requirements, 18 sessionof the decision wasa "five in one" and the impr ovement of overall scheme of reform, will prom ote an integrated and coorreforms and the part

29、y'sconstructionin the area of institutional reform.The "five in one" programme is to achieve acomprehe nsive reform of institutional guarantees forobje ctives ofbuild a well -off society, the smoothprogress of theconstruction of a well-off society and reform the objectives of theprogra

30、mme.One, holding time and place importance on November 9,2013 t o the 18 session of the 12thBeiji ng since 1978, 35,have been 7 plenary session, each time on major issues of political andeconomi c life of thecountry has made important deployment. In accordancewith PRC political practice,often at eve

31、ry session of theCPC Ce ntral Committee in aplenary session washeld immediately after the party'sCongress,on t he theme "personnel",discussing election Central's top leaders, such as the election of the StandingCommittee of thepolitical Bureau, through the Central Committee members

32、, decisions, such as members of theCentral Military Commission.The second plenary session, ishel d in two sessions before the general election, mainly todiscuss anew State personnel issues. But by the third12我從研究表1 發(fā)現(xiàn)了：_號(hào)、 _號(hào)是同一類三角形，因?yàn)開號(hào)、 _號(hào)是同一類三角形，因?yàn)開號(hào)、 _號(hào)是同一類三角形，因?yàn)開 。_ 。_ 。我還發(fā)現(xiàn)了：_ 。匯報(bào)交流，整理提升誰來匯報(bào)你們

33、組的研究情況師（投影教師用研究表）：三角形的共同點(diǎn)是（都有兩個(gè)銳角），不同點(diǎn)是 1 號(hào)、 3 號(hào)三角形有,有一個(gè)角是鈍角有一個(gè)角是直角三個(gè)角都是銳角兩個(gè)角是銳角兩個(gè)角是銳角根據(jù)不同點(diǎn)給三角形命名（課件出示概念），齊讀概念。有一個(gè)角是鈍角有一個(gè)角是直角三個(gè)角都是銳角的三角形叫鈍角三角形的三角形叫直角三角形的三角形叫銳角三角形同學(xué)們拿出你們的學(xué)具給它們分類（指名投影演示分類過程）重點(diǎn)點(diǎn)撥，形成知識(shí)結(jié)論（課件出示集合圖）師：按角分，三角形可以分成 設(shè)計(jì)意圖：三角形按角分類，概念間的關(guān)系簡(jiǎn)單，學(xué)生理解容易。因此，對(duì)于三角形按角分類，教師要全面挖掘這塊內(nèi)容的內(nèi)涵，要把它做強(qiáng)放大。這樣設(shè)計(jì)目的有兩個(gè)：一是

34、從不同點(diǎn)處著手， 讓學(xué)生經(jīng)歷猜想觀察操作比較分類下定義的概念形成過程，一步一步清晰三角形按角的分類的認(rèn)識(shí)。另一目的是讓學(xué)生感悟分類的數(shù)學(xué)思想。 2、按邊分類（ 1）師：三角形除了按角的特點(diǎn)分類，有些三角形的邊也很有特點(diǎn)呢。聽一聽這個(gè)三角形會(huì)說什么？（動(dòng)畫展示）“從邊的特點(diǎn)看我們是一類！”師：同學(xué)們仔細(xì)觀察，這四個(gè)三角形的邊有什么共同特點(diǎn)呢？（ 2）請(qǐng)同學(xué)們?cè)趯W(xué)具袋里把這幾個(gè)三角形找出來 。（每一組任選一個(gè)三角形去量一量或者折一折）（ 3）學(xué)生匯報(bào)。（這幾個(gè)三角形邊的共同特點(diǎn)是什么？）le nary session, each session of theCentral Committee of

35、 national institutions and personnelproblems havebee n arranged, youcan concentrate onnational development and reforms.Previous pl enary session isoften brande d with acentral leading collective, oftenby look ing at the thirdplenum of the initiative to found thecurrent central leadershipcollective g

36、over nance characteristics.From the analysis of theproce ss of e conomic reform inChi na, pl enary session, 12 session, 14, 16 plenary session haveprogrammatic meaning, respectively, marking the four stagesof China 's economic reform, and that the start-upphase of reform, reform, constructionpha

37、 se and perfe cting the Sociali st market economy framework stage of socialist market economy.Previous plenary session topicspropose d to the third plenary sessi onof "taking class struggle as the key link," shifted tosocialist modernization;12 session marked the change from rural tourba n

38、, established with publicownership as the Foundation of a planned commodity economy;13 session at a timewhenbot h the ol d and thenewsystem change , governance a nd re ctify the economic order; 14 . Fair and efficient and a uthoritative Socialist judicial system,safeguard thepeople's interests.L

39、egal authority to uphold theConstitution,dee pening the reform of administrative law enforcement, ensure that the right toexercise judicial power independe ntly and impartiallyaccording tolaw theprosecution,perfecting the running me cha nism of judicial powe r, improve thesystem of judicial protecti

40、on of human rights. Plenary sessi on, Affairs the right to adhere to t he system, and l et the people authority to let t he power run in the S un, is shutup in acage of the systempower policy. Decisi on S cie nce, implementation shoul d beconstructedstrong, supervise the running of powerfulsystem, i

41、mprovethe system of punishingand preventing corruption,promotiinstitutional innovation and i nstitutional protecti on, sound improvement stylenormal system.Plenarysessi on, building a socialist culture in China, enha nci ng nati onalcultural soft power, must adhere to the orientationof advanced Soci

42、alistculture , adhere to the developmentof Sociali st cult urewith Chi nese chara cteristics, adhere to t he peopl e-centred work-oriented, furtherdee pening reform of culture.To improve the cultural management system, establish and improve the modern market system and building modern publi c cultur

43、al service system, improve the levelof culture openi ng. Plenary session, achievi ng developme nt results moreequitablebenefit of all people, we mustspeed up reform of social programs and solve the issues of concern to the pe opl e the mostdirect and real interest, and better meet theneeds of the pe

44、ople.o deepen education reform, improve institutional mechanisms for therapid development of the market economy environment to expl ore public servants 'duty consumption monetization reform hasprovided a good foundation. Thesocialization of rear service workhas been launched, and rapid progress

45、in some places and departments, duty consumption monetization of carrier and a pproach to management has bee n resolve d. Third, in re cent years, exploring the monetization of duty consumption has made some progress, have gained some experience and can provi de reference to thecompre hensive reform

46、 of the system of public serva nts ' dutyconsumption further. Implementing an "honest canteen", standar dize official entertaining management; enhancing the telecommunication expe nse management; elimination of County travel andcountryside subsidies; research "village officials&qu

47、ot; capitalization ma nagement of corporate spendi ng, and so on. Finally, group .18 session to be held inBeijing from Novem ber 9, 2013 to12th. 35 years ago ble w the t hird plenary sessi onof the reform and opening up in the spring breeze,changed, affect the world; t oday, 35 yearslater, in the ey

48、e s of thenation and the worldexpect , again to reform mark China, ushered in the 18 sessi on. XIGeneral Se cretary pointed out that China's reform has e ntered acrucialperiod and the Sham Shui PoDistrict, must be base d on greater politicalcourage and wisdom, l ose no time in deepe ning reform

49、in important fields. Dares to cra ck a hard nut, dares to question the Rapids, w hich dares to break the barrier of ideas, anddare tobenefitcure barriers.Deepening reform andopeni ng up is on schedule to achieve i nstitutional safeguards of the moderately well-off. Under the "five inone" t

50、he Ge neral layout of socialist modernization requirements, 18 sessionof the decision wasa "five in one" and the impr ovement of overall scheme of reform, will prom ote an integrated and coordinatedreforms and the party'sconstructionin the area of institutional reform.The "five in

51、 one" programme is to achieve acomprehe nsive reform of institutional guarantees forobje ctives ofbuild a well -off society, the smoothprogress of theconstruction of a well-off society and reform the objectives of theprogramme.One, holding time and place importance on November 9,2013 t o the 18

52、 session of the 12thBeiji ng since 1978, 35,have been 7 plenary session, each time on major issues of political andeconomi c life of thecountry has made important deployment. In accordancewith PRC political practice,often at every session of theCPC Ce ntral Committee in aplenary session washeld immediately after the party'sCongress,on t he theme "personnel",discussing election Central's top leaders, such as the el