ALEX Lesson Plan


How do clouds form?

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  This lesson provided by:  
Author:Bonnie Howard
System: Madison City
School: Madison Elementary School
The event this resource created for:ASTA
  General Lesson Information  
Lesson Plan ID: 34560


How do clouds form?


The lesson provides an overview of cloud formation. Cloud formation results when warm, humid air rises and cools, causing the water vapor in the air to condense and form clouds. In this lesson, students will conduct an activity that demonstrates how this occurs.

This lesson results from a collaboration between the Alabama State Department of Education and ASTA.

This lesson was modified from NASA series “Investigating the Climate System.  They can be freely downloaded at

 Associated Standards and Objectives 
Content Standard(s):
SC2015 (2015)
Grade: 6
Earth and Space Science
7 ) Use models to construct explanations of the various biogeochemical cycles of Earth (e.g., water, carbon, nitrogen) and the flow of energy that drives these processes.

NAEP Framework
NAEP Statement::
E12.11: Earth is a system containing essentially a fixed amount of each stable chemical atom or element. Most elements can exist in several different chemical forms. Earth elements move within and between the lithosphere, atmosphere, hydrosphere, and biosphere as part of biogeochemical cycles.

NAEP Statement::
E8.14a: Water, which covers the majority of Earth's surface, circulates through the crust, oceans, and atmosphere in what is known as the water cycle.

NAEP Statement::
E8.14b: Water evaporates from Earth's surface, rises and cools as it moves to higher elevations, condenses as clouds, falls as rain or snow, and collects in lakes, oceans, soil, and underground.

Unpacked Content
Scientific And Engineering Practices:
Developing and Using Models
Crosscutting Concepts: Stability and Change
Disciplinary Core Idea: Earth's Systems
Evidence Of Student Attainment:
  • Use models to explain the various biogeochemical cycles of Earth and the flow of energy that drives these processes.
Teacher Vocabulary:
  • Biogeochemical
  • Biotic
  • Abiotic
  • Atom
  • Water cycle
  • Carbon cycle
  • Nitrogen cycle
  • Chemical compound
  • Hydrogen
  • Oxygen
  • Gravity
  • Atmosphere
  • Water vapor
  • Crystallize
  • Transpiration
  • Evaporation
  • Condensation
  • Precipitation
  • Glacier
  • Aquifer
  • Ice sheet
  • Organism
  • Decompose
  • Respiration
  • Element
  • Chemical process
  • Ecosystem
  • Geosphere
  • Carbon dioxide
  • Methane
  • Photosynthesis
  • Fossil fuel
  • Nitrogen
  • Carbon
  • Amino acid
  • Protein
  • DNA
  • Molecule
  • Bacteria
  • Fertilizer
  • Livestock
  • Nitrate
  • The cycle of atoms between living and non-living things is known as a biogeochemical cycle.
  • Biogeochemical cycles interact through biotic and abiotic processes.
  • Biotic involves living or once living things such as plants, animals, and bacteria.
  • Abiotic involves nonliving things like air, rocks, and water.
  • Biogeochemical cycles may include, but are not limited to, the water, carbon, and nitrogen cycles.
  • The water cycle is the continuous process by which water is circulated throughout the earth and the atmosphere.
  • Water is a chemical compound made up of the elements hydrogen and oxygen.
  • Global movements of water and its changes in form are propelled by sunlight and gravity.
  • Energy from the sun drives the movement of water from the Earth (e.g., oceans, landforms, plants) into the atmosphere through transpiration and evaporation.
  • Water vapor in the atmosphere can cool and condense to form rain or crystallize to form snow or ice, which returns to Earth when pulled down by gravity.
  • Water continually cycles among land, ocean, and atmosphere via transpiration, evaporation, condensation and crystallization, and precipitation, as well as downhill flows on land.
  • Gravity causes water on land to move downhill (e.g., rivers and glaciers) and much of it eventually flows into oceans.
  • Some liquid and solid water remains on land in the form of bodies of water, glaciers and ice sheets or can be stored below ground in aquifers.
  • Some water remains in the tissues of plants and other living organisms, and this water is released when the tissues decompose. Water is also released by plants through transpiration and by other living organisms through respiration.
  • Carbon is an element found in the oceans, air, rocks, soil and all living organisms.
  • Carbon is the fundamental building block of life and an important component of many chemical processes.
  • In a process called the carbon cycle, carbon is exchanged among Earth's oceans, atmosphere, ecosystem, and geosphere.
  • Carbon is present in the atmosphere primarily attached to oxygen in a gas called carbon dioxide (CO2), but is also found in other less abundant but climatically significant gases, such as methane (CH4).
  • With the help of the Sun, through the process of photosynthesis, carbon dioxide is pulled from the air to make plant food.
  • Through food chains, the carbon that is in plants moves to the animals that eat them. When an animal eats another animal, the carbon is transferred.
  • When plants and animals die, their bodies, wood, and leaves decay bringing the carbon into the ground. Some become buried miles underground and will become fossil fuels in millions and millions of years.
  • Organisms release carbon dioxide gas through a process called respiration.
  • When humans burn fossil fuels to power factories, power plants, cars and trucks, most of the carbon quickly enters the atmosphere as carbon dioxide gas.
  • The oceans, and other bodies of water, soak up some carbon from the atmosphere.
  • Nitrogen is an element found in living things like plants and animals.
  • Nitrogen is also an important part of non-living things like the air and the soil.
  • Nitrogen atoms move slowly between living things, dead things, the air, soil and water.
  • The continuous process by which nitrogen is exchanged between organisms and the environment is called the nitrogen cycle.
  • Most of the nitrogen on Earth is in the atmosphere as molecules of nitrogen gas (N2).
  • All plants and animals need nitrogen to make amino acids, proteins, and DNA, but the nitrogen in the atmosphere is not in a form that they can use.
  • The molecules of nitrogen in the atmosphere can become usable for living things when they are broken apart during lightning strikes or fires, by certain types of bacteria, or by bacteria associated with bean plants.
  • Most plants get the nitrogen they need to grow from the soils or water in which they live. Animals get the nitrogen they need by eating plants or other animals that contain nitrogen.
  • When organisms die, their bodies decompose bringing the nitrogen into soil on land or into ocean water. Bacteria alter the nitrogen into a form that plants are able to use. Other types of bacteria are able to change nitrogen dissolved in waterways into a form that allows it to return to the atmosphere.
  • Certain actions of humans can cause changes to the nitrogen cycle and the amount of nitrogen that is stored in the land, water, air, and organisms.
  • The use of nitrogen-rich fertilizers can add too much nitrogen in nearby waterways as the fertilizer washes into streams and ponds. The waste associated with livestock farming also adds large amounts of nitrogen into soil and water. The increased nitrate levels cause plants to grow rapidly until they use up the supply and die. The number of plant-eating animals will increase when the plant supply increases and then the animals are left without any food when the plants die.
Students are able to:
  • Use a model of the various biogeochemical cycles and identify the relevant components.
  • Describe the relationships between components of the model including the flow of energy.
  • Articulate a statement that relates a given phenomenon to a scientific idea, including the various biogeochemical cycles of Earth and the flow of energy that drives these processes.
Students understand that:
  • The transfer of energy drives the motion and/or cycling of matter of the various biogeochemical cycles.
AMSTI Resources:
AMSTI Module:
Understanding Weather and Climate

Alabama Alternate Achievement Standards
AAS Standard:
SCI.AAS.6.7- Use a model to explain the water cycle, including evaporation, condensation, and precipitation; recognize that the sun provides the energy which drives the water cycle.

Local/National Standards:


Primary Learning Objective(s):

The students will use a model to construct an explanation for cloud formation. 

Additional Learning Objective(s):

 Preparation Information 

Total Duration:

61 to 90 Minutes

Materials and Resources:

safety goggles
clear plastic bottle with cap
enough water to wet the bottom of the bottle
incense stick (or you can use a paper match)


hot plate

Erlenmeyer flask (2)


rubber band

science journal

Technology Resources Needed:

Interactive whiteboard

internet connection

Student computer (for extension activity)


Background Water vapor; water in its invisible gaseous state, can be made to condense into the form of small cloud droplets. By adding particles such as the smoke enhances the process of water condensation and by squeezing the bottle then releasing it causes the drop in air pressure, which is like air rising to make a cloud. Squeezing the bottle increases the air pressure, like air sinking. This creates a cloud. Evaporation: Water evaporates. Why? The heat from the sun causes water to evaporate and become a vapor that rises up into the atmosphere to become a cloud. You can illustrate evaporation by boiling water in a pan over a hotplate so participants can see the vapor rising. Condensation: All air contains some water in vapor form. Usually, we can't see it but we know it is there by how wet or dry the air feels on our skin as well as our noses and mouths. As warm air rises, it carries water vapor with it. As the air continues to rise, the warm air cools and the pressure eventually decreases enough that the water vapor turns into liquid droplets. These droplets form or condense on smoke and dust particles in the air. The process of changing water vapor into liquid water is called condensation. Vapor turns into raindrops forming a cloud. Precipitation: As more and more droplets of water form into a cloud they start bumping into each other. Some of them stick together and grow to the size of a raindrop (> 1mm in diameter.) As more droplets form into raindrops they get very heavy and eventually fall out of the cloud when the updraft can no longer hold them as a cloud. The cloud bounces and shakes, or precipitates, releasing the droplets in the form of rain, hail, or snow.



As students enter the room have the following prompt written on the interactive whiteboard and ask them to take out their science journal and spend a few minutes generating ideas.

How do you think temperature, pressure or changes in volume are involved in cloud formation? 

Give students time to think about their responses and record their answers in their journal. After 3-4 minutes, have students turn and talk to their neighbors and formulate a response that represents the shared thinking of the people at their table. Bring the entire class back together and have each table group share out their collective ideas.

During their sharing, ask students to share ideas about how water vapor gets into the atmosphere and eventually forms clouds.  

To begin the demonstration, add 5 mL of tap water to the Erlenmeyer flask then place the balloon over the opening to seal the flask then place it on a hot plate.  Heat the water, but do not let it all boil away.  

Carefully remove the flask from the hot plate and ask students to share what they observe.  Have students explain to you why the balloon inflates by drawing on their prior learning from previous labs and investigations.

Repeat the procedure with a second Erlenmeyer flask but this time do not stretch the balloon over the opening until after you remove it from the hot plate. Place the flask into the ice water bath.  If performed correctly, the balloon should invert into the flask.  Again ask students what they think is happening. Relate this back to previous lessons on air pressure. 


Students receive lab materials listed in the Materials section.

Lab Procedure

1. Put on safety goggles.

2. Pour water into the 2L bottle, place the cap on, and shake for 30 seconds.

3.  Squeeze the bottle—

Ask the following questions.

  • What effect does this have on the environmental conditions inside the bottle?

Now release the pressure on the bottle.

  • What effect does this have on the environmental conditions inside the bottle?
  • Did a cloud form?

4. After the smoke from the incense or paper match is placed in your bottle, quickly place the cap on and then repeat Step 2.

  • This time, did the cloud appear when you squeezed or when you released the bottle?
  • What’s happening when you do this (i.e., what condition has been provided for clouds to form)? 

Explain to the students.  Even though we don't see them, water molecules are in the air all around us. These airborne water molecules are called water vapor. When the molecules are bouncing around in the atmosphere, they don't normally stick together.

Pumping the bottle forces the molecules to squeeze together or compress. Releasing the pressure allows the air to expand, and in doing so, the temperature of the air becomes cooler. This cooling process allows the molecules to stick together – or condense – more easily, forming tiny droplets. Clouds are nothing more than groups of tiny water droplets!Students


Students will share their observations with the whole class. 

Ask the participants to recap the entire experiment and discuss what happened in each step.

How was water vapor created? (Water in its invisible gaseous state, can be made to condense into the form of small cloud droplets.)

What happened when smoke was added to the bottle with vapor? (smoke provides the particles) What role does smoke play in creating a cloud in the sky? (By adding particles such as the smoke enhances the process of water condensation.)  

What is air pressure and how did you change the pressure in the bottle? What role does air pressure play in the creation of a cloud? (By squeezing the bottle causes the air pressure to drop. A cloud appeared when you released and disappears when you squeeze.)

Review the roles of vapor, smoke, and pressure in creating a cloud.  


Using knowledge gained from the experiment, students will provide a written explanation on how clouds form in the atmosphere. Each student will then draw their own illustration of cloud formation in their science journal. Students create an illustration to model the roles of vapor, smoke, and pressure in creating a cloud. 


Assessment Strategies

Assessment during this activity is formative to determine if students can use a model to construct an explanation for cloud formation. The teacher will observe student participation during the lab activity and review completed cloud formation illustration. 

A rubric can be used to assess participation in the lab activity. The rubric can be found on page 13 entitled rubric activity two on the following website 


Cloud seeding is a process by which particles are dispersed in the air in an attempt to increase the amount of precipitation in a particular area. Research the history and effectiveness of cloud seeding. Provide at least three examples where it has been used. In addition, provide three arguments for or against the use of cloud seeding


Ask students to write and/or illustrate what they did during this activity and what they learned from their participation in the activity.  

View the Special Education resources for instructional guidance in providing modifications and adaptations for students with significant cognitive disabilities who qualify for the Alabama Alternate Assessment.