第一步：引入本单元的话题
方案一:
可以直接利用课本热身部分提供的问题来引出话题，如：要求学生discuss in groups which science subjects are part of medicine, biochemistry, geophysics or astronomy, and what are the most important skills we need to be real scientists? 这一方案开门见山,不仅能很快切入本单元的主题,而且问题指向明确,学生比较容易展开话题。
方案二：
可以利用其他更为生动、灵活的方式如：以How life began on the earth?为任务主题，要求四人小组讨论，自由交谈引入话题，要求自圆其说，并稍后呈现小组讨论结果。（关于宇宙和人类的起源，不同的文化有不同的传说。传说与科学理论不同，它甚至不是科学假设，但因为是故事，有情节且趣味性强，因而为学生所爱。）老师要充分估计学生可能的讨论结果，准备相关的图片、视频或材料，以备小组呈现结果时用。或者让学生提前准备，把其中的个别故事排演成英文短剧，展示给学生看。
1) Legend: Pangu creates the world
2) Science: The Big Bang（大爆炸）
Scientists believe that around 15 billion years ago, a huge explosion happened, creating our universe.
There are several famous scientists such as Newton, Einstain and Stephen Hawking. They all have their own opinions on the universe.
第二步：观看关于太阳系的短片( about two minutes )。目的在于把生命的起源从各种传说故事中慢慢地回归到科学事实上。同时也为课文提供了深刻的背景知识。
第三步: 课文的整体听力理解，完成单项选择。
1.在播放课文听力材料之前，让学生浏览听力理解的问题。
1）Why was the earth different from other planets?
A. It produced a lot of heat.
B. The water remained.
C. Water disappeared.
D. It was the oldest planet.
2） Why was life able to develop on the earth but not on other planets?
A. The earth had a solid shape.
B. The earth did not have harmful gases in its atmosphere.
C. The water stayed on the earth but not on other planets.
D. The earth was not too hot and not too cold.
3）Why was it necessary for plants to grow before animals?
A. Animals needed plants to protect them from the sun.
B. Plants provided oxygen for animals to breathe.
C. Animals could hide from hunters in forests.
D. It was easier for plants to grow.
4）What problem is caused by human beings?
A. They exist every where on the earth.
B. They cause global warming.
C. They find new methods of growing crops.
D. They enjoy hunting and fishing.
2.让学生听录音答题。
3. 让学生确认答案。
4. 让学生讨论听力理解答案。
第四步: 分段细读文章，检测理解。
1. 带着问题细读第一段。
Suggested questions:
1） How did water come into being on the earth?
2） What is the significance of the presence of water on the earth?
Suggested answers:
1)The explosion of the earth produced water vapour which turned into water when the earth cooled down.
2）It allowed the earth to dissolve harmful gases into oceans and seas.
2.双人互动：讨论并找出文中表述事实或观点的句子各两个。
Fact 1_______________________________
Fact 2_______________________________
Opinion 1_____________________________
Opinion 2_____________________________
参考答案：
Fact 1：Dinosaus died out long before human beings developed on the earth.
Fact 2: They are putting too much carbon dioxide into the atmosphere, which prevents heat from escaping from the earth into space.
Opinion 1: They are the cleverest animals because they have larger brains than any other creatures on the earth so far.
Opinion 2: The earth may become too hot for life to live on it.
第五步: 概括全文。
1. 用自己的话简单地概括文章大意。
2. 按照课文填空：
After the “Big Bang”, the earth was just a cloud of _______ dust. It __________ loudly with fire and rock, which were _________to produce the water vapour, ___________ and other gases. Then small plants grew. They ___________and filled the oceans and seas with oxygen. Many millions of years later the first green plants began to ________on land. When the plants grew into forests, ________ appeared for the first time. They produced young generally by _________eggs. When dinosaurs disappeared, ________ became more important. Now small clever animals with__________ appeared and ___________ all over the world. As time went by they covered the earth and they are putting too much carbon dioxide into the__________, which ________heat_________ the earth into space. Whether life will continue on earth for millions of years to come will ________whether this problem can be solved.
相关分类