Hands-on Activity Air Quality and Particulate Matter

Quick Look

Grade Level: 2 (K-2)

Time Required: 3 hours 15 minutes

(Part 1: What is air quality (AQ) and the Air Quality Index (AQI)? (60 min)

Part 1 Make Wind Streamer (30 min to prepare)

Part 2 Make PM Catcher (30 min to prepare, leave outside 5 days to collect PM)

Part 3: Record Wind and PM Data (20 min each day)

Part 4: Analyze PM Data Table & PM Catcher, and Class Reflection (60 min))

Expendable Cost/Group: US $2.00

Group Size: 3

Activity Dependency: None

Subject Areas: Earth and Space, Number and Operations, Science and Technology

NGSS Performance Expectations:

NGSS Three Dimensional Triangle

An Air Quality Index (AQI) Chart.
Figure 1. Air Quality Index (AQI) Chart
Copyright © https://climatekids.nasa.gov/air-pollution/


This activity introduces students to the relationship between air quality and wind. Students work together to learn about the color-coded Air Quality Index (AQI) chart that describes levels of air pollution for a primary transportation-sourced air pollutant—particulate matter (PM)— and what to do during high pollution days. Student teams design and build a PM Catcher, a prototype for collecting wind-blown PM 10 particles outdoors. Over a week, student teams will record the daily PM levels using AirNow.gov at their school location (or nearest town or city). Concurrently, student teams will leave their PM Catchers in the same vicinity to collect any wind-blown PM 10 particles. The class will then review the PM AQI data and observe their PM Catchers and count the number of PM 10 particles attached to the surface. Ways to stay safe on high air pollution days are also presented.
This engineering curriculum aligns to Next Generation Science Standards (NGSS).

Engineering Connection

Clean air is essential for everyone and the environment. Air quality engineers are one type of environmental engineer, and they help to monitor, control, and most importantly, reduce air pollution to help improve public health. Like other engineers, air quality engineers perform a variety of tasks as part of their job including:

  • Modeling and understanding pollution and its sources
  • Monitoring emissions and compliance with applicable regulations
  • Designing and implementing air quality improvement solutions

Air quality engineers have natural sciences knowledge and expertise, such as chemistry, biology, physics, and mathematics, to inform their decision-making processes.

Learning Objectives

After this activity, students should be able to:

  • Recall that particulate matter (PM) affects air quality and health.
  • Design-build-test a prototype to collect wind-blown particulate matter.
  • Record the Air Quality Index (AQI) PM levels for healthy and unhealthy air from AirNow.gov.
  • Observe the PM Catcher for any wind-blown PM 10 particles on it.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS Performance Expectation

3-ESS2-1. Represent data in tables and graphical displays to describe typical weather conditions expected during a particular season. (Grade 3)

Do you agree with this alignment?

Click to view other curriculum aligned to this Performance Expectation
This activity focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices Disciplinary Core Ideas Crosscutting Concepts
Represent data in tables and various graphical displays (bar graphs and pictographs) to reveal patterns that indicate relationships.

Alignment agreement:

Scientists record patterns of the weather across different times and areas so that they can make predictions about what kind of weather might happen next.

Alignment agreement:

Patterns of change can be used to make predictions.

Alignment agreement:

NGSS Performance Expectation

K-2-ETS1-1. Ask questions, make observations, and gather information about a situation people want to change to define a simple problem that can be solved through the development of a new or improved object or tool. (Grades K - 2)

Do you agree with this alignment?

Click to view other curriculum aligned to this Performance Expectation
This activity focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices Disciplinary Core Ideas Crosscutting Concepts
Ask questions based on observations to find more information about the natural and/or designed world(s).

Alignment agreement:

Define a simple problem that can be solved through the development of a new or improved object or tool.

Alignment agreement:

A situation that people want to change or create can be approached as a problem to be solved through engineering.

Alignment agreement:

Asking questions, making observations, and gathering information are helpful in thinking about problems.

Alignment agreement:

Before beginning to design a solution, it is important to clearly understand the problem.

Alignment agreement:

NGSS Performance Expectation

K-ESS3-3. Communicate solutions that will reduce the impact of humans on the land, water, air, and/or other living things in the local environment. (Grade K)

Do you agree with this alignment?

Click to view other curriculum aligned to this Performance Expectation
This activity focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices Disciplinary Core Ideas Crosscutting Concepts
Communicate solutions with others in oral and/or written forms using models and/or drawings that provide detail about scientific ideas.

Alignment agreement:

Things that people do to live comfortably can affect the world around them. But they can make choices that reduce their impacts on the land, water, air, and other living things.

Alignment agreement:

Designs can be conveyed through sketches, drawings, or physical models. These representations are useful in communicating ideas for a problem's solutions to other people.

Alignment agreement:

Events have causes that generate observable patterns.

Alignment agreement:

Suggest an alignment not listed above

Materials List

Per student:

Per group:

  • Part 1: Make Wind Streamer:
    • Light-weight streamer material (e.g., crepe paper, ribbons, paper strips, etc.) cut into 3’ strips
    • Paper plate
    • Ruler
    • hole punch (or scissors used by teacher)
    • Markers or crayons
    • Compass to determine north
  • Part 2: Make PM Catcher (per student):
    • Notecards (3”x5”)
    • Round solid object less than 3” in diameter to trace a circle onto the notecard (option to pre-trace for younger students)
    • Hole punch (or scissors used by teacher)
    • 12” pieces of string or yarn
    • Permanent marker
    • Petroleum jelly
    • Clear packing tape
    • Hand lens or magnifying glass
  • Part 3: Wind and PM Data Collection:
    • Pencil
    • Datasheet
    • Wind Streamer (per team)
    • AirNow.gov PM 2.5 daily reading for school location (or nearest area)
  • Part 4: Analyze Wind & PM Data Table and PM Catcher, and Class Reflection:
    • Wind and PM data table (datasheet section 2)
    • PM Catcher and PM Catcher grid (datasheet section 3)
    • Hand lens

Worksheets and Attachments

Visit [www.teachengineering.org/activities/view/cub-2632-air-quality-particulate-matter-k-2-activity] to print or download.

Pre-Req Knowledge

A basic understanding of interpreting simple keys and numeracy (ones, tens, hundred values)

Basic knowledge of particulate matter and its effects on health.


Clean and healthy air is essential for all living things, but how do we know how clean and healthy the air is each day? In the previous lesson, we learned that air carries very small particles of solids and liquids called particulate matter, or PM for short. Air flows due to changing weather conditions, especially by blowing wind, which can transport PM air pollution.

For this activity, we are going to work as teams of Environmental Engineers to explore air quality or AQ for short, and together we will find out:

  • How can we measure how clean (healthy) the air is that we breathe?
  • Does the air carry particulate matter (PM)?
  • What should we do when the air is dirty (unhealthy)?

Student teams will design and build a Wind Streamer to observe the direction of the wind, and a PM Catcher to observe PM that is in the air and carried by the wind. Over a period of five days, students will use the AirNow.gov website to record the level of PM 2.5, which are very fine particles that can cause health issues if breathed in, at their school location or nearest area.

Let’s get started and work together to build our AQ know-how!



Air Quality is monitored by the U.S. Environmental Protection Agency and communicated through the EPA AirNow.gov, as well as the National Weather Service forecasts.

One primary air pollutant, which comes from fossil fuel-burning transportation sources that pose significant human health risks, is particulate matter (PM).

PM is formed from natural sources, such as wildfire and volcanic eruptions, and human-made sources when fossil fuels are burned, for example by vehicles and industries, and the emissions that are released into the air.

Breathing PM irritation and damage to the respiratory system. Sensitive groups, which include the young, elderly, active people, and those with respiratory diseases, such as asthma, are even more sensitive to breathing PM. When inhaled PM 2.5, which is 30x smaller than human hair and not visible to the naked eye, is particularly dangerous since it is small enough to be absorbed into the bloodstream and can affect organs including the heart and lungs. PM 10 are larger particles that can be seen, such as dust, pollen, and ash, that are not healthy to breathe in but are less dangerous than PM 2.5.

The US EPA Air Quality Index (AQI) is a six-stage chart that communicates the level of PM in the air so people can take appropriate action to stay safe and healthy. When the AQ is below 100 the AQI is green or yellow, which means the air is healthy to breathe. When the AQ is 100 or higher, the AQI is orange, red, purple, or brown, which means the air is increasingly unhealthy to breathe.

When the AQ rating is 100 or higher, it is advised to take the recommended precautions at the relevant level to protect one’s health, such as limiting time outdoors and refraining from strenuous activity.

To limit transportation-related PM pollution, it is advised that people limit the use of fossil-fuel-powered vehicles, such as passenger vehicles, and carpool, take public transportation, bike or walk, especially during daylight hours.

Before the Activity

  • Locate the specific location(s) for safely recording wind direction and placing out PM Catchers, preferably, a flat, accessible, open area.
  • Collect materials for each group.
  • Prepare Air Quality and Particulate Matter Datasheets for each student.

With the Students

Part 1: What is Air Quality (AQ) and the Air Quality Index (AQI)?

  1. As a warm-up and to review what students learned about particulate matter (PM) in the previous lesson, show students the Wildfires in the West Cause Air Pollution video (show to 1:33). Have a think-pair-share on the discussion questions listed in the first section of the datasheet for this portion.
  2. Next, introduce students to the concept of air quality (AQ) and the Air Quality Index (AQI) by showing the Why is Coco Orange? Video (English and Spanish caption options) and/or reading the accompanying picture book (Spanish option, too). Have a think-pair-share on the discussion questions listed in the first section of the datasheet for this portion.

An Air Quality Index (AQI) Chart.
Figure 1. Air Quality Index (AQI) Chart
Copyright © https://climatekids.nasa.gov/air-pollution/

  1. Tie in concepts from the Coco video/book to the AQI chart, review the columns together as a class.  In partners, have students complete the grade-level AirNow AQ flag activity sheet referring to the AQI chart on the datasheet. Ask students to volunteer to share their answers to reinforce the connection between AQ colors and the different levels of air health. 

A flyer for the Air Quality Flag Program.
Figure 2. AirNow
Copyright © Air Quality Flags

  1. Explain to the class that they will work together as teams of Environmental Engineers to design objects to collect data on wind and air quality around their school. Show examples of the Wind Streamer and PM Catcher. Assign students into teams of 2-4 to undertake the challenge.

Part 2: Make a Wind Streamer to determine the wind direction.

  1. Show students the Wind Streamer video.
  2. Show the students the materials they will need to build their own Wind Streamer. Hand out all materials except the streamer materials to each group. Guide teams step-by-step as they design and build their Wind Streamer:
    1. Have students draw a large “+” sign in the middle of the paper plate.
    2. Next, draw the cardinal compass directions on the board. On their plates, have teams label the top line “N” for north, the right-side line “E” for east, the bottom line “S” for south, and the left-side line “W” for west.
    3. Assist students in hole-punching the edge of the plate at the N, E, S, W labels.
    4. Show the streamer materials. Tell teams to discuss together and then choose the material they think will work best for blowing the wind but will also be durable to withstand strong winds from the streamer choices. Assist teams to thread and knot the streamer material through the punched holes on the plate.
    5. When using the Wind Streamer outdoors, demonstrate to students to face north (teacher uses a compass to determine direction) and hold their Wind Streamer by the south location and keep it level. 
    6. The direction that the streamers are flowing from (not towards) is the wind direction that they will record on their datasheet when collecting data.

A wind streamer.
Figure 3. Wind Streamer in action

Part 3: Make a PM Catcher to trap wind-blown particulate matter.

  1. Ask students what they recall about particulate matter (PM) from the previous lesson. Explain that some particles are too small for our eyes to see (PM 2.5), but other particles are larger (PM 10), which we can see such as dust, pollen or ash. PM comes from natural and human-made sources. PM can cause health issues if breathed in, especially PM 2.5 since it is so small and can go deep into our lungs. Explain to students that they are going to collect data on the amount of PM 10 in the air around their school.
  2. Show students an example of a finished PM Catcher what the different parts of the example and how it works to trap PM that is carried through the air by wind.
  3. Show students the materials available to build their PM Catcher. Explain that teams will have a choice of how they are going to trap PM with their PM Catcher using either tape or petroleum jelly.
  4. Assist student teams step-by-step through the design and build process:
    1. Pass out a notecard to each student. Have students trace a circle (less than 3’ dia.) or hand draw a circle, in the approximate center of the notecard. Next, have students write their names on the back of their cards (the teacher can prep the cards for younger students).
    2. Hole punch along the width of the card about ¾ of an inch from the edge of the notecard.
    3. Thread the string or yarn through the hole and tie a knot to hand the PM Catcher.
    4. Explain that students have two options for designing a way to catch PM—tape or petroleum jelly. If the tape is used, the traced circle will need to be carefully cut out of the card with teacher help, as needed. If petroleum jelly is used, a thin layer will be smeared inside the circle only. Part of the activity is to test which option catches the most PM. 

Different PM catcher options.
Figure 4. PM Catcher Options
Copyright © Jennifer Taylor

  1. Go outside on the school grounds and discuss where students think are places where sources of PM air pollution are located (e.g., idling car and bus areas, nearby roads (remind students about traffic safety), bare ground (dust, dirt), etc.). Decide on a couple of safe and accessible outdoor places to place their PM Catchers to collect particulate matter. Suggestions:
    1. Single location with multiple PM Catchers at each cardinal direction
    2. Several locations have a few PM Catchers at each cardinal location. It’s best to place the PM Catchers outside preferably a meter or two above ground.
  1. Leave the PM Catchers outside for 5 days (avoid when rain or snow is forecasted).

Part 4: AQ Data Table: Record Wind and PM Data

  1. While the PM Catchers are collecting particulate matter from the air, collect wind and PM 2.5 data, as listed on AQ Data Table in the second section of the datasheet. Model an example first then guide students through the daily data collection process for five days:
    1. Record the date and head outdoors.
    2. Use the Wind Streamers to determine the wind direction and circle the direction on the compass icon.
    3. Ask students to estimate the strength of the wind and check the corresponding box.
    4. Use the AirNow.gov website (in class) or smartphone app (outdoors) to look up and record the day’s record the PM 2.5 level and the corresponding PM 2.5 air quality color on the datasheet. This information is located below the AirNow.gov AQ dial image in the “Current Air Quality” section. 
    5. Based on each day’s PM 2.5 level, indicate if it’s an Air Quality Alert day.

A screenshot of the AirNow.gov dashboard.
Figure 5. Screenshot of the AirNow.gov dashboard
Copyright © AirNow.gov

  1. After 5 days, go back outside and pick up the PM Catchers.

Part 5: Analyze PM Data Table & PM Catcher, and Class Reflection

  1. As a class, complete section 4 of the datasheet. Review the Air Quality Index (AQI).
  2. Lead the class as teams work together on the section questions. Ask teams to share their responses to each question in a class discussion.
  3. Have teams review their Air Quality data table where they recorded wind and PM 2.5 data. Tally up the number of green and yellow (good AQ days) and orange, red, purple (bad AQ days).
  4. Have students share the results of their PM Catchers. Keep track of # of PM pieces on tape vs Vaseline to see if one design is more effective than the other.
  5. Wrap-up the activity with a class reflection by having students share their thoughts on the following discussion questions:
    • What did you enjoy in learning about Air Quality (AQ)?
    • Explain what PM is in your own words.
    • How do the AQ colors help us know how good or bad the air is?
    • What is one thing we should do when the AQ is not healthy?
  1. Tell students: Fantastic team work! Your engineering team has tracked particles and air quality in your neighborhood, and now knows the importance of clean air and what to do on high air pollution days.


air pollution: A mixture of solid particles and gases in the air from human-made sources such as car exhaust (emissions), chemicals from factories, and natural sources such as dust, pollen, and mold.

air quality: A measure of how clean or dirty the air is.

Air Quality Index (AQI) chart: The US Environmental Protection Agency (EPA) index for reporting air quality.

particles (aerosols): Very small solid or liquid droplets, which can be found floating in the air.

Particulate Matter (PM): Air pollution made of very small particles in the air that come from natural sources (wildfire smoke, dust) and human-made sources (vehicle and factory exhaust).

pollutant: A chemical or biological substance that harms water, air, or land quality.


Pre-Activity Assessment

Interpreting Data and Numerical Data: As a whole class, ask students to mark a number line from 0-300 by 100s. Next, ask students to identify which number has the greatest value, the least value, where random numbers between 0-300 are located on the number line, etc.

Activity Embedded (Formative) Assessment

Worksheet Think-Pair-Share: Scaffold students’ learning by having them work as a whole class as they complete the Air Quality and Particulate Matter Datasheet, as directed in the Procedure section. Together as a class, students identify and record the PM AQI from AirNow.org and the general wind direction and wind strength of their particulate matter collector on their datasheet for a week or more.

Post-Activity (Summative) Assessment

Problem Solving: As a whole class, review the datasheet PM AQI data and the number of PM 10 particles counted on the PM Catcher. Have a class discussion about the data and how the information relates to how clean (healthy) or dirty (unhealthy) the air was during the activity time frame.

Making Sense: Have students reflect on the science concepts they explored and/or the science and engineering skills they used, plus questions or ideas they have by completing the Making Sense Assessment.

Investigating Questions

Essential Questions:

  • How can we measure how clean (healthy) the air is that we breathe?
  • Does the air carry particulate matter (PM)?
  • What should we do when the air is dirty (unhealthy)?


Particulate matter is a primary air pollutant, which comes from transportation sources and affects people’s health:

The National Weather Service provides model forecast guidance for particulate matter and ozone twice daily and smoke predictions once daily for the next 48 hours. State and local agencies use NWS model guidance to issue air quality forecasts that weather forecast offices (WFOs) help disseminate. Air quality forecasts of unhealthy (code orange) or worse air quality that are shared with WFOs get displayed on NWS warning maps as air quality alerts. 

The weather can significantly impact air quality since different aspects of the weather affect the amounts of ozone and particulates that are present in a specific area.  Sunshine, rain, higher temperatures, wind strength, air turbulence, and mixing depths all affect pollutant concentrations.

  • Wind strength, air turbulence, and mixing depth all affect how pollutants disperse or spread out from an area
  • Sunshine can cause some pollutants to undergo chemical reactions, resulting in the development of smog or ozone
  • Higher air temperatures can increase chemical reactions in the air
  • Rain typically results in less pollution since it washes away the particulate matter and can also wash out pollutants that are dissolvable

When Air Quality Alerts are in effect, there are actions people can take to stay safe and protect their health:

  • Stay informed about air quality conditions in your area. Information is provided by EPA, NWS, and the media
  • Choose a less-strenuous activity
  • Shorten and take more breaks during outdoor activity
  • Reschedule activities to the morning or to another day
  • Move your activity inside where ozone levels are usually lower
  • Spend less time near busy roads
  • If possible, avoid driving gas-powered vehicles during times of poor air quality

Here’s what you can do to help make the air cleaner:


Safety Issues

When outdoors, be aware of traffic safety concerns, especially if placing PM Catchers near PM pollution sources (e.g., parking lots, bus lanes, etc.)

Troubleshooting Tips

Check that students Wind Streamers and PM Catchers are placed away from structures and trees so that the prevailing wind direction can be observed and PM collections is not affected.

Activity Extensions

AirNow.gov Air Quality Curriculum and Resources: https://www.airnow.gov/air-quality-flag-program/schools/

AirNow.gov Air Quality Flag Program: https://www.airnow.gov/air-quality-flag-program/

AirNow.gov “For Teachers” section: https://www.airnow.gov/education/teachers/

AirNow.gov “For Students” section ages 4-7: https://www.airnow.gov/education/students/

AirNow.gov Coloring Page: https://www.airnow.gov/publications/air-quality-flag-program-classroom-curriculum/coloring-page/

AirNow.gov Bird’s Eye View Lesson: https://www.airnow.gov/publications/air-quality-flag-program-classroom-curriculum/birds-eye-view-lesson-plan/

Air Pollutions: Seeing Small Specks from Space resource and activity: https://earthobservatory.nasa.gov/blogs/eokids/wp-content/uploads/sites/6/2018/09/AQ-PM25-09-10pm2_508.pdf

Activity Scaling

For grades 3-5, see the Air Quality and Weather Connections activity.

Additional Multimedia Support

In class, bookmark AirNow.gov and Weather.gov to access air quality and weather data for the section 2 data table.

Download AirNow.gov and Weather.gov apps for use outdoors.


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AirNow.gov. Accessed July 29, 2021. (Source of Activity Guides Publications) https://www.airnow.gov/publications/activity-guides-publications/

AirNow.gov. Accessed July 29, 2021. (Source of Air Quality Index and Air Quality and Health information) https://www.airnow.gov/aqi-and-health/

AirNow.gov. Accessed August 18, 2021. (Source of ways to make the air cleaner and what to do on air quality action days) https://www.airnow.gov/education/what-you-can-do/

Armstrong, Patricia. Bloom’s Taxonomy. 2021. Vanderbilt University Center for Teaching. https://cft.vanderbilt.edu/guides-sub-pages/blooms-taxonomy/

GLOBE.gov. Accessed October 8, 2021 (Source of PM Catcher activity adapted from GLOBE What’s Up in the Air activity) https://www.globe.gov/web/mission-earth/overview/air-quality-initiative/learning-activities

Lunar and Planetary Institute. Accessed. October 1, 2021. (Source to make Wind Streamer). https://www.lpi.usra.edu/education/explore/ice/activities/ice_earth/wind-streamer/

McFadden, Christopher. How Environmental Engineers Help Fight Air Pollution. August 3, 2020. Interesting Engineering. https://interestingengineering.com/how-environmental-engineers-help-fight-air-pollution

Michigan.gov. Accessed October 15, 2021. (Source to make PM Catcher). https://www.michigan.gov/documents/explorelabscience/Measuring_Air_Pollution_Experiment_559910_7.pdf

Science Museum of Virginia. Accessed October 15, 2021. (Source to make PM Catcher). https://smv.org/documents/49/Whatsintheair.pdf

STARnet. Accessed October 6, 2021. (Source of Wind Streamer design-build) https://www.youtube.com/watch?v=vIAHXC5z6ug

US EPA. Accessed August 18, 2021. (Source of particulate matter information) https://www.epa.gov/pm-pollution

Weather.gov. Accessed July 29, 2021 (Source of particulate matter information, weather impacts on air quality, what to do when air quality is poor, and ways to make air cleaner) https://www.weather.gov/wrn/summer-article-clearing-the-air

Other Related Information

This activity requires the following resources:


© 2022 by Regents of the University of Colorado


Jennifer Taylor

Supporting Program

Integrated Teaching and Learning Program, Pre-College Engineering Education, University of Colorado Boulder


This curriculum was developed under National Science Foundation grant number 1941524. Any opinions, findings, and conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

This curriculum was developed with support from the AEROKATS and ROVER Education Network (AREN) (Henry/NNX16AB95A). AREN is a NASA Science Mission Directorate Science Activation (SciAct) Program.

Last modified: October 23, 2023

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