1、本课建议安排二课时授完。第一课时讲光源、光的直线传播和光速;第二课时讲光的折射、反射现象及其在实际中的应用。 2、讲“光源”时,可先让学生例举哪些物体能发光,然后从中抽象出“光源”的概念。学生举例时很可能将太阳、月亮一并称为发光的物体。我们可以告诉学生,月亮本身不发光,它不是光源。在下面讲到光的反射时,再告诉学生月亮光是由太阳照射到月 1, this lesson is proposed to arrange two hours granted. The first class tells the light source, the light of the linear transmission and speed of light; the second class tells the light refraction, reflection and its application in practice. 2, say “light”, you can let students give priority to what objects can light, and then abstract out the “light” concept. When students give examples, they are likely to refer to the sun and the moon as luminescent objects. We can tell the students that the moon itself is not luminous, it is not a light source. Speaking of light reflections below, tell the students that the moon's light is shone from the sun to the moon