高中英语第四册Unit 13, Senior 2教案
Step II Warming up.
Teacher show the students the globe, and ask many questions.
Task 1: Do some experiments following the instructions in the book.
Experiment 1 Cover a glass of water with a piece of thick paper. Put one hand on the paper and turn the glass upside down. Slowly take your hand away from the paper.
Experiment 2 Pour water and vegetable oil into a glass.
Experiment 3 Put a piece of chalk in water for 24 hours.
Task 2: While doing these experiments , the students are asked to observe carefully and try to describe the phenomena.)