1、Unit 21 Human Biology Lesson 1 Chewing Gum Teaching Aims: 1. To improve the reading ability of the students and help them study the structure of the text and understand the text wholly. 2. To enrich the students knowledge about the advantages and disadvantages of chewing gum and encourage them to ta
2、lk about the problem of students chewing gum in the school Teaching Difficulties and Emphasis: 1. Help the students to find more advantages and disadvantages of chewing gum. 2. Help the students to carry out the discussion. Teaching methods: 1. Task-based teaching . 2. Individual and group work ; Di
3、scussing . Teaching Aids: Computer and worksheets Teaching Procedures: Step 1: Leading -in 1. Show the picture of a NBA star (Micheal Jordan). 1) Who is the man 2) What is the man eating? Step 2:Reading 1. Do you like chewing gum? 2. Is it good or bad for our health?- To chew or not to chew 3. Liste
4、n to the tape carefully and divide the text into several parts Part1 ( para 1 ): introduction Part2 ( para 2-4 ): the advantages of chewing gum Part3 ( para 5-7 ): the disadvantages of chewing gum Part4 ( para 8 ): conclusion 4. Find the advantages and disadvantages of chewing gum in the text. Advan
5、tages Disadvantages 1.helping people fight bad breath 2.helping people stop tooth decay 3.helping people lose weight 4.helping smokers give up smoking 1.making digestion more difficult 2.causing feelings of sickness or headaches 3.leading to stomach sickness 4.making people neglect brushing their te
6、eth 5.Find more advantages and disadvantages of chewing gum (show some pictures or videos). 6. Decide if the following statements are true or false. 1). Diet specialists seldom inform us that it is important to chew our food properly. ( F ) 2).Chewing gum can not fight bad breath. ( F ) 3). If you h
7、ad chewed sugar-free gum regularly for two years, you would have lost up to 5kilos. ( F ) 4). If people chewed 50 times per minute for 24 minutes, 70 kilocalories were burned. ( T ) 5). Chewing gum can help smokers give up their bad habit more successfully. ( T ) 6). When we chew gum, it will not ca
8、use our bodies to produce digestives juices. ( F ) 7). Chewing gum for long periods of time will make our stomach become tense. ( T ) 8). Chewing sugar-free gum must cause the number of young people with bad teeth to rise. ( F ) 9). On balance, it would be better to chew gum. ( F ) 7. Fill in the bl
9、anks with the proper words which are in the text. On one hand, chewing gum can fight bad breath. Some dentists believe that sugar-free gum helps to stop tooth decay. Gum controls peoples appetite so it can help people to lose weight. Gum can also contain medicine. It helps smokers give up their bad
10、habit successfully. On the other hand, chewing gum has its negative side. Diet specialists say chewing starts the production of stomach acid and digestive juices. It will make digestion more difficult and may cause feelings of sickness or even headaches. Further, chewing gum for long periods of time
11、 may lead to stomach sickness. On balance, wed better forget chewing gum, eat healthy foods and never start smoking. So that we can live a healthy life. 8. Show the picture about the pollution in the Tiananmen Square on National Days. 1). Where is it? 2). What are they doing? 9. Introduce something
12、about the news Step 3:Discussion Nowadays many students like chewing gum in the school. Some students chew gum after a meal to get a good smell. However, some chew gum in the class or even when they are having a test then throw it anywhere. Do you think it right for us students to chew gum in the school? Give your reasons. Step 4:Homework Write an article about your discussion: Do you think it right for us students to chew gum in the school?
