Lesson 26 Keep the Candle Burningppt课件教学实录

Lesson 26

Keep the Candle Burning

┃教学整体设计┃

【教学目标】

【教学重难点】

重点：掌握本课单词，用英语准确地描1.能够熟练记忆、使用match，use up等述实验过程，通过听、读，反复呈现，实验单词和短语。

操作突出重点。

2.能够用英语描述和解释描述本课的实难点：通过示范，实验操作来突破难点。

验。

【课前准备】

3.在学习中，集中注意力，并积极思考，蜡烛、烛台、大的广口瓶、一个浅盘、培养热爱科学的精神。

一些水和一个打火机4.让学生树立主动向他人求教的意识。

┃教学过程设计┃

教学过程

一、创设情境，切入主题

Step 1：Warming up

What’s this？(It’s a candle.)Yes，it’s a burning candle.We will have an interesting class.Can you guess what we will do in this class？There are some things that may be used in an experiment.Do you want to know what will happen？Today we’ll learn Lesson 26：Keep the Candle Burning. 设计意图：利用带来的教具，凭着学生对科学强烈的求知欲和好奇心，学习本课的新词，并鼓励他们表述实验。

二、展开过程，探究新知

Step 2：Presentation

1.Watch，Say and Fill (1)What do we need? We need a candle，a candle holder，a big glass jar，a shallow dish，some water and a lighter. (2)What do we do? First，________ the candle ________ the candle holder. Then ________ the candle holder ________ the dish. Third ________ the dish ________ water. Fourth，________ the candle. Fifth，________ the candle ________ for two minutes. 2.Imagine and Predict If I put the jar over the candle until the top of the jar rests on the dish，what will happen? I’m not sure./I’m sure it will...

I think... Maybe... 3.Do，Observe and Answer Put the jar over the candle carefully until the top of the jar rests on the dish. (The candle stops burning.The water rises up.) 4.Then do Exercises 1 and 2 on Page 69 设计意图：教师示范实验，同时描述实验过程，让学生熟悉实验流程，并让学生在听的过程中填出关键词，为下一步做实验做好基础，并讨论会发生什么。体现本单元主题Talking About Science。

Step 3：Listen，read and think

1.Why did the candle stop burning?

Because it has ________ the oxygen in the air.(used up) 2.Why did the water rise? Because the force outside the jar is ________ than the force inside the jar.(stronger) 3.How far did the water rise? Because there is about ________ oxygen in the jar，so the water rises and fills about ________ of the jar.(one fifth，one fifth) Step 4：Project

1.Do the experiment in groups Read about the experiment in this lesson.With a group of classmates，practice the experiment.Do your experiment in front of the class.Don’t forget the following things：

First，describe your experiment. Second，ask the class what they think will happen. Third，do the experiment. Finally，ask the class if the result is what they expected. 组长分配任务，一人写实验报告，一人做实验，其他人用英语描述实验过程，必须用英语描述，否则实验为失败，小组间比赛，实验成功且完成快的组，获得一颗星奖励。

2.Write the experiment report Step 5：Explain the language notes of the text to the class

1.Keep the candle burning！让蜡烛燃烧！

keep... burning 使……燃烧。keep sth.(sb.)doing使某物(某人)保持做某一动作状态。

2.use up用光，耗尽。表示完全，彻底。

3.one-fifth五分之一。

分数的表达：

分数由分子及分母两部分构成。用英语表达时，分子用基数形式，分母用序数词形式。若分子为1时，则分母的序数词为单数形式；若分子大于1时，则分母的序数词用复数形式。

如：1/3，one third，三分之一；1/5，one fifth，五分之一；3/4，three fourths，四分之三；2/5，two fifths，五分之二

三、布置作业

Write the experiment that you have learned in this unit.

┃教学小结┃

【板书设计】

Lesson 26

Keep the Candle Burning

keep...burning使……燃烧

use up用光，耗尽

one-fifth五分之一

分数的表达