(
课件网) Unit 5 Lesson 25 Let's Do an Experiment! 1.学习目标 3.重点探究 2.自主学习 学习导航 5.当堂检测 6.课堂总结 4.拓展提升 新课导入 (1)Do you like science (2)What kinds of experiments have you done in science class (3)If you hold a jar that is filled with water upside down, what will happen 学习目标 1.掌握本课新单词: science, experiment, fill, prove, scientific, method. 掌握本课短语: do an experiment, fill…with, cover…with, turn…upside down, be (not) sure… 2.增强对科学实验的兴趣 自主学习 experiment jar upside scientific method pour correct raincoat force pressure conclude 实验;试验 广口瓶; 罐子 上部;上边 科学的 方法; 办法 倒出；倾倒 正确的；恰当的 雨衣 力量；迫使，强迫 压力，压强；挤压 得出结论；断定；推断出 重点探究 Think about it! 1. What kinds of experiments have you done in science class 2. If you hold a jar that is filled with water upside down, what will happen Danny, Jenny and Brian are in the lab. Brian: Let' s do an experiment. I fill a jar with water. I cover the top with a piece of cardboard and hold it there.Then I turn the jar upside down and take my hand off the cardboard.Can you guess what will happen Danny: I think the floor will get wet.We should do this experiment outside, Brian. Jenny: I think the cardboard will hold the water. Danny: I don' t think so. Jenny: You think the water will pour out, Danny. I think the water will stay in the jar. Let's test which theory is correct. Brian: Good idea, Jenny. That's called the scientific method. Jenny: I am so sure of my theory that Brian can do the experiment over your head and I know you won't get wet. Danny: Well, let' s try it! Brian: Are you ready, Danny Danny: No! Wait! (He puts on a raincoat and sits down.) Now, I think I' m ready. Jenny: Brian, take your hand off the cardboard. Danny: No!(Danny closes his eyes tightly, and Brian takes his hand off the cardboard.The water stays in the jar:) Jenny: See, Danny! Danny: How is that possible Brian: The force of the air keeps the water in the jar. It is strong enough to hold the water. Danny: Wow! Brian: So what have we discovered Jenny: We have discovered that the air pressure helps the cardboard hold the water in the jar. Brian: Right. What do you conclude, Danny Danny: I conclude that air is stronger than I thought. (1)Where does Danny think they should do the experiment He thinks they should do the experiment outside. (2)What keeps the water in the jar The force of the air. (3)Is Jenny sure of her theory How do you know Yes,she is. Because she is so sure of her theory that Brain can do it. (4)Why does Danny put on his raincoat In order not to get wet. (5)What does Danny conclude He concluded that air is stronger than he thought. 1 Read the dialogue with the following questions. Let's Do It! 2 Read the experiment.Put the sentence in the correct order on page 67. 2 5 1 3 4 6 Let's Do It! Put a piece of cardboard over the jar. The jar of water is upside down , but the wa ... ...
