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Why can you smell things you can't see?

Particle Models
Lesson narration:
English Spanish
Scroll for prep
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DISCUSS: What do you think could cause thousands of people to suddenly smell maple syrup?

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Slide Image
DISCUSS:
How do you think an object’s smell gets from the object to your nose?
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Step
01/16
You’ll work with a partner.
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Step
02/16
Get your supplies.
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Step
03/16
Cut along the dotted line of your Spinners sheet.
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Step
04/16
Use a pencil to poke a hole in the center of each spinner.
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Step
05/16
Put the fastener through the big opening of a paper clip. Put it
through the hole in the Spinner. Fold the arms of your fastener
down. Make sure there is a gap between the paper clip and the paper.
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Step
06/16
Make your map. Cut along the dotted line of the Cookie Particle
Paths sheet. Then add stickers to connect the two pages together.
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Step
07/16
Decide who will be the Spinner first and who will be
the Mapper first. You’ll get a chance to do both jobs.
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Step
08/16
Spinner: Use both spinners to find out where your particle will go
in the first turn. Mapper: Draw on the map where your particle goes.
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Step
09/16
Work together to move the particles on the map and see where
they go.
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Step
10a/16
Discuss these questions.
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Step
10b/16
Here’s what we said.
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Step
11/16
Get your final supply.
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Step
12/16
Let’s investigate what happens with a strong wind.
On the Direction Spinner, cross out all arrows that DON’T point right.
On the Number Spinner, cross out “1”, replace with “5”.
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Step
13/16
Switch jobs with your partner.
Spinner: If your spinner lands on a crossed-out arrow, spin again.
Mapper: Use a marker to draw where each particle goes.
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Step
14/16
Discuss.
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Step
15/16
Discuss.
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Step
16/16
Discuss.
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DISCUSS:

Can you think of any situation where particles in the air might be a bad thing?

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Slide Image

matter


1 of 7

anything that takes up space and has weight; can be in different forms such as solid, liquid, or gas
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particle


2 of 7

a very tiny thing, too small to be seen
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Slide Image

solid


3 of 7

matter that is rigid and holds its shape
Slide Image

liquid


4 of 7

matter that takes the shape of its container

gas


5 of 7

matter that spreads out to completely fill a space
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states of matter


6 of 7

the different forms of matter that include solid, liquid, and gas
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Slide Image

model


7 of 7

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
Why can you smell things you can't see?
Particle Models
Lesson narration:
English Spanish

Activity Prep

Print Prep
This lesson was revised on June 13, 2026. Here is a link to the previous version.
In this lesson, students investigate why people all across New York City suddenly started smelling a mysterious maple syrup scent. In the activity, Particle Paths, students develop a model of how particles move in order to figure out how a delicious smell can travel through the air to our noses.
Preview activity

Vocabulary

Vocabulary

Student slideshow: English | Spanish

Teacher printout: English & Spanish
What you’ll need for student
Cookie Particle Paths printout 1 per pair
Spinners printout 1 per pair
Colored Pencils
1 per pair
Markers
A different color than the colored pencil.
1 marker per pair
Scissors
1 pair per pair
File Folder Labels (Stickers)
2 stickers per pair
Paper Clips
2 paper clips per pair
Paper Fasteners
2 fasteners per pair
Prep Instructions

We suggest students work in pairs. Homeschool students can work on their own.

Organize Supplies for Easy Distribution

Students will need supplies at two different steps during the activity. We recommend organizing supplies for easier distribution. In Step 2, each pair of students will need the following:

Step2
In Step 11, each pair of students needs a marker that is a different color than the colored pencil.

Spinner Troubleshooting

If a spinner is not working, check the following:

There is space between the paper clip, the fastener, and the paper.

The fastener’s prongs go through the larger loop of the paper clip, not the smaller one.

No paper scraps from the hole puncture are stuck in the fastener or paper clip.

Standards

Jump to

Exploration

15 mins

Hands-On Activity

30 mins

Wrap-Up

10 mins

Extend this lesson

Unit Reading

Unit Reading

The Great Molasses Flood

In this reading, students learn the story of a chemical reaction that caused a huge molasses tank to explode in Boston in 1919.

Mini-lessons

Mini-lessons

You can elaborate student learning and engagement with Mystery Science mini-lessons.

  • Why do icebergs float? In this mini-lesson students explore how particles too small to be seen can help us understand why giant icebergs float!

If you are in an NGSS state, this mini-lesson supports the DCI PS1.A: Structure and Properties of Matter

Transcripts

Credits
 
Chemistry Lesson 2: Why can you smell things you can't see?

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