Get a free trial until June 30, 2026!
New members get full access to our science units, hands-on activities, mini-lessons, & more!

New members get a full, free trial through June 2026!
Back > Share
Where do fallen leaves go?
Web of Life Unit | Lesson 3 of 7
Back > Share

Where do fallen leaves go?

Web of Life Unit | Lesson 3 of 7
Lesson narration:
English Spanish
Scroll for prep
Video trouble?
Slide Image
DISCUSS:
Where do you think the dead leaves that fall in the forest go?
What could you do to find out?
Video trouble?
Step
01/20
You’ll work with a partner.
Video trouble?
Step
02/20
Get your supplies.
Video trouble?
Step
03/20
Cut out your Suspect Cards and Leaves along the dotted lines.
Put your Suspect Cards in a pile to the side.
Put your Leaves on your Leaf Pile sheet.
Video trouble?
Step
04/20
Lay out Evidence Board sheets in front of you. Put the sheet with
the “Suspect 1” box on top of the sheet with the stripes. Overlap the
stripes so that the Suspect boxes on the two sheets line up.
Video trouble?
Step
05/20
Place the Red Fox card in the “Suspect 1” box on your Evidence
Board. Read it with your partner. Underline what happened to the
leaves. Circle who else was near the leaves.
Video trouble?
Step
06/20
When the timer starts, rip your leaves in half. Rip as many as you can
until the timer stops. Make sure all of your leaf pieces are on your
Leaf Pile sheet.
Video trouble?
Step
07/20
Put the Mouse card in the “Suspect 2” box on your Evidence Board.
Read the card with your partner. Underline what happened to the
leaves. Circle who else was near the leaves.
Video trouble?
Step
08/20
When the timer starts, rip your leaf pieces in half. Rip as many as you
can until the timer stops.
Video trouble?
Step
09/20
Put the Worm card in the “Suspect 3” box on your Evidence Board.
Read the card with your partner. Underline what happened to the
leaves. Circle who else was near the leaves.
Video trouble?
Step
10/20
Put some leaf pieces on top of the Worm card. Then, when the timer
starts, rip your leaf pieces in half. Rip as many as you can until the
timer stops.
Video trouble?
Step
11/20
Pour water on your leaf pile and watch what happens. Or go to the
next slide.
Video trouble?
Step
12/20
Discuss:
Video trouble?
Step
13/20
Draw rain clouds in the box above your leaf pile with your blue crayon
to help you remember that your leaf pieces are now wet.
Video trouble?
Step
14/20
Put the Fungi card in the “Suspect 4” box on your Evidence Board.
Read the card with your partner. Underline what happened to the
leaves. Circle who else was near the leaves.
Video trouble?
Step
15/20
Take some of your leaf pieces and put them on top of your Fungi
card. When the timer starts, rip your leaf pieces in half.
Video trouble?
Step
16/20
Put the Bacteria card in the “Suspect 5” box on your Evidence Board.
Read the card with your partner. Underline what happened to the
leaves.
Video trouble?
Step
17/20
Take most of your leaf pieces and put them on top of the Bacteria
Suspect Card. When the timer starts, rip your remaining leaf pieces
in half.
Video trouble?
Step
18/20
Get the rest of your supplies.
Video trouble?
Step
19/20
Discuss. Then, answer question 1 on your Solve the Case worksheet.
Video trouble?
Step
20/20
Discuss. Then, answer question 2 on your Solve the Case worksheet.
Video trouble?
Video trouble?
Slide Image
DISCUSS:
What do you see happening in real life that matches your model?
What's different?
Video trouble?
Slide Image
DISCUSS:
What kinds of dead stuff or leftover waste from these living things could be food for decomposers?
Video trouble?
Slide Image
Slide Image

organism


1 of 14

any living thing
Slide Image

environment


2 of 14

a living thing’s surroundings, including other living things and non-living parts like soil, water, and air
Slide Image

soil


3 of 14

covers the Earth's surface; made of tiny rocks and material from dead plants and animals

matter


4 of 14

anything that takes up space and has weight; can be in different forms such as solid, liquid, or gas
Video trouble?
Slide Image

model


5 of 14

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
Slide Image

evidence


6 of 14

Information that can be used to support or reject an idea
Slide Image

decomposer


7 of 14

a living thing that can break down dead organisms or animal waste

decompose


8 of 14

the process of breaking down dead organisms or animal waste
Video trouble?
Slide Image

compost


9 of 14

decayed plant material that can be used as fertilizer
Slide Image

fungus (fungi)


10 of 14

a living thing that is a decomposer, such as a mold or mushroom
Slide Image

mushroom


11 of 14

a type of fungus that usually has a stalk and cap
Slide Image

mold


12 of 14

a type of fungus that often decomposes food
Slide Image

microscope


13 of 14

a tool used to see very tiny things up close
Slide Image

bacteria


14 of 14

an organism that is usually a decomposer; some cause illness
🎉 That’s it for this lesson! How did it go?

Extend this lesson

Vocabulary

Unit Reading

Assessments

View all extensions
Sign up now for more great lessons!
Sign up
Lesson narration:
English Spanish

Lesson details

Grade 5

Ecosystems & The Food Web

Decomposers & Matter Flow

5-LS2-1

Activity Prep

Print Prep
THIS LESSON WAS REVISED ON JUNE 14, 2025. Here is a link to the previous version.
In this lesson, students develop a model to describe the flow of matter between living things and the environment, with an emphasis on decomposers. In the activity, Decomposer Detectives, students gather information from suspects on the forest floor, and model the decomposition process of fallen leaves in order to solve the mystery of why those leaf piles seem to disappear.
Preview activity

I have a Mystery Pack

Evidence Board worksheet 15 copies
Leaves & Leaf Pile worksheet 15 copies
Solve the Case worksheet 15 copies
Suspect Cards worksheet 15 copies
Crayons
Any shade of blue. Markers or colored pencils will also work.
Details
15 crayons
Scissors
30 pairs
Clear Plastic Cups (10 oz)
1 cup
Plastic Plates (10")
1 plate
Prep Instructions

We suggest students work in groups of pairs. You will need access to water for this activity.

Prep Your Solve the Case worksheets Cut each of these worksheets in half so that each student has a 1/2 sheet.

Jump to

Exploration

10 mins

Hands-On Activity

30 mins

Wrap-Up

15 mins

Lesson details

Grade 5

Ecosystems & The Food Web

Decomposers & Matter Flow

5-LS2-1

Share this lesson

Student link

Google Classroom

Email parents

Slow internet or video problems?
Credits
 
Ecosystems Lesson 3: Where do fallen leaves go?

How did the lesson go?
Terrible OK Good Great Terrific!

How can we improve it?

If you'd like our team to reply to you, please Contact Support instead.

Thanks for your feedback! If you have a question or need help, please contact us. Please consider sharing your review:

Sorry the lesson didn’t go well. We read every single review in an effort to improve our Mysteries.

Thanks for letting us know. We’ll wait to ask you for feedback until after you've actually taught it.

Thanks for the feedback! We read every single review in an effort to improve our Mysteries.

Is the video not playing properly?

Please follow these steps:

  1. Very rarely a video will fail to completely load in your browser. Try to reload this page to see if that fixes the problem.
  2. If reloading does not help, try our other video player .
  3. If the video still fails to play, open this video in a new tab and please let us know you’re having trouble. We want to fix this issue for you.

Close

How can we help you?

💡For purchasing info, see our Pricing Page

This episode is locked

This lesson is not included in your limited access.

View pricing

This episode is locked

Your membership is expired. The archive of past Mini Lessons is not included in your limited access.

View pricing