Module5ALessoninaLab【美文阅读】HowtocreatearocketballoonTocreatearocketballoon,you'llneedthefollowingitems:aballoon(anysize),apieceofstring(10to25feet),astraightdrinkingstraw(吸管),tape.First,youhavetocreatea“track”fortherocketballoontorunon.Youbeginbytyingoneendofthestringtoatree,post,chair,oranyotherstrongsupport.Thenslide(使滑动)thefreeendofthestringthroughthedrinkingstraw.Tietheotherendofthestringtoanothersupport(generallyatthesameheight).Makesurethestringistaut(绷紧的)whentieddown.Movethestrawtooneendofthestring.Filltheballoonwithair.Holdthenecktightlytokeepitfull.Usingtwopiecesoftapetoattachtheballoontothestraw.Themouthoftheballoonshouldpointtowardthenearestsupport.Thenreleasetheballoonandwatchitgo!Whenthemouthoftheballoonisheldclosed,theairintheballoonhasnowheretogo,soitpushesbacktokeeptheballoon'sshape.However,sincethemouthisopenwhenyoureleaseit,theairhassomewheretogo.Theairpushesoutthemouthoftheballoon.Sincetheairisnowmoving,therocketballoonalsomoves.ThisfollowsNewton'sThirdLawofMotion(foreveryactionthere'sanequalandoppositereaction)．Thereisfriction(摩擦)betweenthestringandthestraw,butthestrawismadeofmaterialthat'ssmoothandtheweightoftheballoonandstrawislight,sotheoverallfrictionalforceisverysmall.Itisthesamewhenrocketswork.Theyburnfueltopushmatteroutthebackforcefully.Therocketmovesinresponsetothis.Sincearocketweighsmuchmorethanaballoon,ofcourse,ittakesmorefueltogetitmoving.【诱思导学】1．Doyoulikedoingscientificexperiments?Whatarethestagesofascientificexperiment?.【答案】Yes,Ido.Thestagesareasfollows:aim—method—result—conclusion.2．Whatwillhappenwhentheairintheballoonisreceased?.【答案】Whentheballoon'smouthisopen，theairwillpushtheballoontomove.PeriodⅠPreviewing(教师用书独具)●教学目标本课时主要是通过学生对学案所给出的内容的学习，了解本课文中所出现的词汇，初步了解课文以及相关的背景知识，对下一堂课对课文的全面理解起到一个铺垫作用。●教学地位该部分列举了与科技、实验有关的词汇，并设计了三个练习活动。通过这三个活动，学生可以初步熟悉这些词的意义，为以后的各项学习活动做好准备。(教师用书独具)●新课导入建议(1)Askthestudentstoreadthroughthequestionsquickly.Howdoeswaterexist?Ifyouheatametal,whatchangewillhappen?Whatissteelmadefrom?Whatistheearth'ssurfacemainlycoveredby?Howfaristhesunfromtheearth?Howoldistheearth?Whichislarger,theearthorthemoon?(2)Askthestudentstolistentothetapeandfindouttheanswerstothesequestions.(3)Putthestudentsintopairsorgroupsoffourandcomparetheiranswers.(4)Callbacktheanswersfromtheclass.Suggestedanswers：Waterexistsasasolid,aliquidandagas.Whenyouheatametal,itexpands.Steelisamixtureofironandothersubstances.Twothirdsoftheearth'ssurfaceiswater.Thedistanceofthesunfromtheearthis150,500,500km.Theearthis4.6billionyearsold.Theearthisfortyninetimeslargerthanthemoon.●教学流程设计导入新课。→学生阅读“美文阅读”与“诱思导学”(见学案第57页)。→学生就“美文阅读”进行讨论，统一答案。→让学生快速阅读课文(见课本第44～45页)，并完成“篇章结构”(见学案第57页)。→师生共同讨论并统一答案。→学生再次阅读课文(见课本第44～45页)并完成“语篇理解”(见学案第58页)。→学生共同讨论，并让学生发表各自见解，最后统一答案。→学生再次仔细阅读课文(见课本第44～45页)，进行深度理解，并完成“课文缩写”(见学案第58页)。→老师指导学生讨论，共同找出答案。→让学生完成“知识初探”部分(见学案第58页)。→学生讨论，并让学生代表发表他们讨论得出的答案。老师予以更正。→让学生根据所给出的表格进...
