Step One: 确定目标：
知识目标：学习一些自然知识以及掌握各种数的写法和读法.
能力目标：能和同学进行有关科技和实验的讨论.
情感目标：让学生学会热爱科学.
Step Two: 基础自学：
㈠Ask the students to answer the following questions.
① How does water exist?
② If you heat a metal; what change will happen?
③ What is steel made from?
④ What is the earth’s surface mainly covered by?
⑤ How far is the sun from the earth?
