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Precipitation Lesson Outline
Bell Work: Ask students to list and draw all the different types of precipitation they can think of with their lab partner. Then ask students to share with the class and record the answers they give on the board.
Getting Ready to Teach the Lesson:
Purpose – To gain an understanding of the different types of precipitation, how they are caused, and how they affect the earth.
Objective – When called on in class the student will be able to identify the forms of precipitation correctly and explain the processes that cause precipitation. They will also be able to recognize and describe the effects these different types of precipitation have on our communities.
Review – Draw the cycle below (without labels) on the whiteboard and have students label and explain the different parts of the water cycle.
Anticipatory Set – http://www.youtube.com/watch?v=GStFOzp7FUE
* Stop video at 1:19
Lesson Content

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Input/New Knowledge – Lecture Notes are provided on separate sheet
Modeling – Glass pane and colored water, Refer to Lecture Notes
Checking for Understanding – Ask students the following questions and have them raise their hands to answer orally.
Who can list for me the four types of precipitation?
(Rain, Hail, Snow, and Sleet)
Can someone define coalescence for me?
(Coalescence is the formation of large droplets by the combination of smaller droplets)
Activities
What is the difference between warm cloud precipitation and cold cloud precipitation?
(In warm cloud precipitation, raindrops form by coalescence. In cold cloud precipitation, water is supercooled and freezes when it impacts a solid object called freezing nuclei.)
Guided Practice/Extension – Making Hail Lab
“As an activity today we will be looking at how hail is made.”
Purpose – Understanding how hail is formed.
Process – Working in groups of two or three students will follow the directions on the lab handout and answer the questions at the bottom of the page.
Product – By following directions correctly students should have created a small hailstone in their test tube and answered worksheet questions.
*Students have their own copy of the lab. These are printed and stacked in on
the front table.
*You may point out the materials in the back and then allow them to read the
directions and complete the tasks in groups of two or three.
*Materials will be laid out on the back counter. Ice chips will be in the freezer
in my office.
Independent Practice – Students will find a news article about precipitation off the
Internet using their laptops. Once they have read the article they will write up a one-

Lile, 3 page summary of the article and response. Below are links to a few different articles that students may use or the can have the option to choose their own.
Purpose – Students should use this as a global connection. It is helpful for students to be able to see different types of precipitation are affecting communities around the world.
Process – Students will choose one of the articles listed below or another relevant article of their choosing and write a one page summary and response.
Product – A better understanding of how weather affects areas outside of our community and page long article critique. The response should be no longer than a page.
Nature Notes: Nevada’s wild extremes in precipitation http://elkodaily.com/lifestyles/nature-notes-nevada-s-wild-extremes-inprecipitation/article_a832857c-a918-11e2-91dc-0019bb2963f4.html
New study: A warming world will further intensify extreme precipitation events http://www.noaanews.noaa.gov/stories2013/20130403_ncdcextremeprecipitation study.html
Heavy Precipitation Eases Drought in Northern Plains, Midwest http://online.wsj.com/article/BT-CO-20130418-
711086.html?mod=googlenews_wsj
While Precipitation Slows, Floodwaters Rise http://www.wuwm.com/news/wuwm_news.php?articleid=12295
*Students do NOT have a hand out of these instructions so please write them on the board and encourage students to record them in their notebooks or planners.
Wrapping-Up the Lesson
Closure – Have a few students share what they found in their articles and discuss as a class the ecological and economical impact these types of precipitation have had.
Evaluation – Students will be evaluated based on their production of test tube hail, well thought out paper, and completed worksheet with correct answers. Their understanding will be validated based on their answers to checking for understanding questions as well.
Homework – If students do not finish their article review in class they can turn it in at the beginning of the next class.

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Works Cited
Allison, M. A., DeGaetano, A. T., & Pasachoff, J. M. (2010). Earth Science (Teacher's
Edition ed., pp. 555-559). Austin, TX: Hold McDougal.
Tarbuck, E. J., & Lutgens, F. K. (2006). Earth Science (Teacher's Edition ed., pp. 520-
522). Upper Saddle River, NJ: Pearson Prentice Hall.
* Precipitation affects us in more ways than we know. This is just one example of how precipitation affects us can you think of any more? (Have students shout out answers)
- Car accidents because of snow, ice, and rain
- Power outages
- Dangerous sidewalks and streets
- SNOW DAYS!
Precipitation Lecture Notes
* Power point will have main points but the notes are more elaborate.
Please ask students to take notes on the lecture and let them know that they will be quizzed over it. They may use their computers if they wish.
Anticipatory Set: KABOOYAW!!
*Ask the students to verbally point out the economical impact the hail made in this woman’s life.
1.
Precipitation a.
Can anyone define precipitation for me in your own words? (Water that falls from the sky.) b.
Definition: any moisture that falls from the air to Earth’s surface
2.
Four Major Types a.
Rain – Liquid precipitation b.
Snow – Solid Precipitation c.
Sleet – Rain that falls through a layer of freezing air d.
Hail – Lumps of ice
3.
Minor Types a.
Drizzle – Rain smaller than 0.5 mm b.
Glaze Ice – Thick layer of ice that is caused by rain not freezing until it hits the ground, caused by an “ice storm”
4.
Causes of Precipitation a.
Cloud droplets grow in volume one million times b.
Warm Cloud Precipitation – Coalescence c.
Cold Cloud Precipitation – Supercooling
5.
Coalescence a.
Formation of a large water droplet from many other smaller droplets

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Warm Cloud Precipitation c.
Rain
* Modeling – Take the plastic tablet off the front counter and using the dyed water in the spray bottle, spray the tablet until droplets form and begin to run down the front. Talk about how a similar thing happens inside the cloud. “As the water droplets are pulled downward by gravity they coalesce with or “pick up” other droplets that cause it to become heavier until it falls to the earth.”
6.
Supercooling a.
Water in the liquid state below 0 degrees b.
Freezes when it impacts a solid object c.
Freezing nuclei – Solid particles in the air ex. Salt particles, dust d.
Water vapor condenses on the freezing nuclei and creates ice crystals e.
Ice crystals grow in size until they are heavy enough to fall to the earth as snow
7.
Hail Formation a.
Produced in cumulonimbus clouds b.
Can anyone describe what a cumulonimbus cloud looks like? (Like big white puffy cotton balls, cotton candy, etc.) c.
Small ice pellets collect more supercooled water droplets on their way down to the earth and can sometimes be pushed back upward by the wind causing the process to start over again. d.
The bottom picture shows the layers of ice that formed as it was pulled down by gravity and then pushed back up by the updraft.
Ask the “Checking for Understanding” questions listed above in the Lesson Outline portion.

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Purpose
Students will simulate the creation of hail.
Materials
Salt
Water
600-mL beaker
Stirring rod
Large test tube
Ice chip
Procedure
Put 15 g of salt and 50 mL of water into a 600-mL beaker. Stir the water until the salt has dissolved. Clean a large test tube thoroughly and put 15 mL of cold water in it. Place the test tube in the beaker. Add crushed ice to the beaker until it is almost full. Watch this! Take the test tube out of the beaker and drop a small chip of ice into it.
Hypothesis
What do you expect to happen?
The ice chip will become larger.
Critical Thinking
What did you observe?
The ice chip grew.
Why did this happen?
Because the water surrounding the ice chip had become supercooled so when it came in contact with the ice chip it clung to it.
Where in the atmosphere do we see this formation take place?
Cold Clouds