小學(xué)數(shù)學(xué)-小數(shù)加減法教學(xué)課件設(shè)計(jì)

一、情境導(dǎo)入“健健”出生時(shí)的胸圍是0.77米。“壯壯”出生時(shí)的胸圍比健健多0.03米?！敖〗　斌w長(zhǎng)是0.72米，“壯壯”出生時(shí)的胸圍是多少？“壯壯”體長(zhǎng)是0.76米，“壯壯”出生時(shí)的體長(zhǎng)比“健健”長(zhǎng)多少？壯壯出生時(shí)的胸圍比健健多0.03米。健健出生時(shí)的胸圍是0.77米。二、合作探索“壯壯”出生時(shí)的胸圍是多少？0.77+0.03=（米）“健健”的胸圍是0.77米。“壯壯”比健健多0.03米。幾個(gè)0.01豎式試一試幾個(gè)0.1十分位二、合作探索答：“壯壯”出生時(shí)的胸圍是0.8米。0.770.03+00.8“壯壯”出生時(shí)的胸圍是多少？0.77+0.03=（米）8返回個(gè)位百分位二、合作探索“健健”的體長(zhǎng)是0.72米?！皦褖选钡捏w長(zhǎng)是0.76米?！皦褖选背錾鷷r(shí)的體長(zhǎng)比健健長(zhǎng)多少？0.040.76-0.72=（米）答：“壯壯”出生時(shí)的體長(zhǎng)是0.04米。0.760.72-0400.04+0.720.76驗(yàn)算：-0.620.

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+0.55試一試70.320.94832你會(huì)計(jì)算0.32+0.55和0.94-0.62嗎？相同數(shù)位要對(duì)齊，小數(shù)加減法也可以按整數(shù)加減法的的計(jì)算方法去計(jì)算。計(jì)算結(jié)果能化簡(jiǎn)的要化簡(jiǎn)。小數(shù)加減法的計(jì)算方法：0.77+0.030.80.76-0.720.04二、合作探索你會(huì)計(jì)算3.75+3.4和1.3-1.25嗎？3.75+3.453.75+3.4=二、合作探索7.15117.1.3二、合作探索1.3-1.25=0.051.25-050﹒.0被減數(shù)位數(shù)比減數(shù)小，根據(jù)小數(shù)性質(zhì)，在被減數(shù)的末位寫0補(bǔ)位你會(huì)計(jì)算3.75+3.4和1.3-1.25嗎？小數(shù)點(diǎn)對(duì)齊，數(shù)位就對(duì)齊了

怎樣又快有好的，對(duì)齊數(shù)位？二、合作探索先把小數(shù)點(diǎn)對(duì)齊，再按照整數(shù)加減法的計(jì)算方法進(jìn)行計(jì)算，計(jì)算結(jié)果能化簡(jiǎn)的要化簡(jiǎn)

通過(guò)剛才的計(jì)算，你能用一句話，總結(jié)出小數(shù)加減法的計(jì)算方法嗎？二、合作探索三、自主練習(xí)1.火眼金睛辨對(duì)錯(cuò)。4.6+2.85.45147617.066.56.41－6.50.565.9-3.582.482.320×××三、自主練習(xí)2.計(jì)算。1