課程目標 Lesson objective: 

1. 學習如何過濾汙水

2. 測試不同液體的PH值與TDS值(總溶解固體值)

3. 學生能完整並正確表達觀測結果

課程任務 Lesson Assignment:

1. 1st period: Discuss the water cycle. How does the earth purify water naturally? Handout of water cycle followed by activity for practice. 

2. 2nd period: Discuss methods people use to purify water. Filtration plants. Make a purifier out of a 2-liter bottle.

3. 3rd period: Test the PH and TDS of different water sources around the school. Add Vinegar and dissolved baking soda for comparison. 

4. 4th period: Assessment Day 

     What is the PH/TDS of ________?

     The PH/TDS of ________ is __________.