1. Walk-In Copy the question and answer in sentences: If a lake is a body of water surrounded by land, how can there be layers in a lake? Explain!

2. Answer A lake contains three layers of different temperatures, due to the amount of sunlight each layer gets. The top layer is warm. The middle layer is a transition, or changing, layer. The bottom layer is cold.

3. Write today’s title: The Pros and Cons of Dams

4. What is a dam? A dam is a barrier built by humans on a river, to stop the water from flowing. Water behind the dam collects and forms a man-made lake, or RESERVOIR. Beyond the dam, there is either no water, or less water, flowing, allowing the amount to be controlled.

5. The Hoover Dam This is a marvel of engineering on the Colorado River! What advantages do you think it gives the people of Nevada, Arizona and California?

6. Advantages and Disadvantages What could be good about having a dam on a river? What could be bad about it?

7. Video Clip Watch this light-hearted video clip of what can happen when a dam is created!video clip

8. Video Clip Watch this video clip about large dams in the United States and around the world.video clip Focus on the pros and cons of dams. After the video, make a T-chart of Pros and Cons, and list as many things as you remember. Viewing expectations: No talking. If you are talking or off-task, you may be sent to ISI Timeout for the rest of the period.

9. T-Chart Write your name on your half-sheet of paper. Make a T-chart, with Pros of Dams on the left side, and Cons of Dams on the right side. List as many things on each side that you can remember. This is good background for the homework project coming up! If there is time, use your T-chart to write a summary paragraph on the back of your half-sheet.