Hold the Mold!

Grade Level Summary Background:

5-8 Students will learn about the different What is mold?
kinds of mold and how it grows. They Mold is the common name for many
Subject Areas will learn the health effects of mold and kinds of tiny organisms called fungi.
Science how to help avoid the growth of mold. There are thousands of types of molds
Health that can be found indoors and
Objectives: outdoors. Different molds will grow in
Duration Students will: colonies, living on dead organisms
20 minute intro Understand what mold is and how it such as decaying plants and animals,
15 min experiment prep grows as well as non-living materials such as
10 min activity discussion Observe the growth of different kinds buildings, food, fabric and books.
2 weeks for experiment of food molds & understand how to Some molds even thrive on living
20 minute wrap up identify and prevent mold growth. organisms as parasites. Molds play
an important part of the natural
decaying process of living organisms
Setting Materials: in the natural world. However, they
Classroom Small paper plates may present a health risk in indoor
Sealable sandwich bags environments.
Skills 5 apples or other fruit: quartered Molds need moisture to thrive and
Observation Sliced bread, halved usually grow and reproduce spores in
Collecting data Spray bottle with water damp or moist places. Light and
Communication Permanent marker to ID bags temperature also impact mold growth
Tape to seal bags in different locations such as showers,
Vocabulary Observation Worksheets kitchens, damp basements, and
Mold Materials Tip: Use older apples or fruit around windows. Mold travels by
Spores “seconds” from a local orchard or releasing spores into the air. Spores
Fungi
market are reproductive structures that allow
Humidity organisms such as fungi to spread
National Science Standards: and survive in almost any
Unifying Concepts and Processes environment. Mold spores float
Related Websites
- Changes, constancy, and through the air, landing on and
www.epa.gov/mold/
www.epa.gov/children
measurement interacting with thousands of living
www.cdc.gov/mold/ - Evidence, models, & and non-living objects.
explanation
Science as Inquiry
- Abilities necessary to do
scientific inquiry
Science in Personal & Social
Perspectives
- Personal health
- Science and technology in
society
- Natural hazards
History & Nature of Science
- Science as a human endeavor Figure 1. Mold spores magnified.
- Nature of science

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What does mold look like? Procedure:
Mold grows in many sizes, textures, and colors such Warm-Up:
as white, black, green, blue, and orange. Spores Ask students if they have ever seen mold.
are released by mature mold that varies in color, or Discuss with students what mold is, where it
may not be colorful at all. Each mold growth can be comes from, and what purpose it serves.
different. Show students a picture of moldy bread.
Introduce them to the sources and health
effects of mold.

Activity
To gain a clear understanding of what mold is,
looks like, how it grows and spreads, students
will conduct an experiment where they will
grow contained household mold samples to
observe and document.
1. Have students work in pairs.
2. Each pair gets a paper plate and a sealable
Figure 2. Moldy bread. plastic bag. Have students write their name
and the date on their bag.
What are the health impacts of mold? 3. Students should then put their paper plate
Spores from mold growth, while natural, can also inside the bag, but not seal it yet.
pose health risks. Some people, with or without 4. Instruct students to place one slice of apple
allergies, are very sensitive to mold or may become and one half slice of bread on their plate,
sensitive to mold from single or repeated exposure. inside the bag.
Molds, mold spores, and pieces of mold may impact 5. Students should use the water spray bottle
a person’s health by causing minor irritations such to moisten their bread with one spray into
as a runny nose or itchy, watery eyes to major the bag.
health concerns such as difficulty breathing, asthma 6. Students then seal their bag and place tape
attacks, infections, fever, and major skin irritations. over the seal.
The best way to reduce and prevent mold growth is 7. Place bags on a shelf where they will get
to control moisture. To reduce mold growth in warm, but not hot and can sit still for two
homes, schools and other buildings, it is important weeks.
to keep humidity levels low, between 30-60%. To 8. Instruct students that they are going to
reduce excess moisture that mold needs to grow, observe their experiment bag for mold
it's also important to repair leaks, completely clean growth. Each student gets worksheets to
and remove any existing mold growth, ventilate observe and record their observations and
bathrooms, kitchens and basements that are more data each day for two weeks. Worksheets
prone to damp conditions, and use a dehumidifier to include questions to help guide
remove moisture from the air if necessary. Outside, observations and a place for students to
mold may grow in damp, shaded areas with lots of sketch a simple drawing of their
leaves or compost. People who are sensitive to observations. Note: Sketches will not be
molds should be careful to avoid such places and shared at the end of the experiment. They
areas prone to lots of mold growth. are for the student to use as a data tool.
Teachers may elect to use digital cameras
When cleaning and removing mold at home or in to record daily mold growth progress and
school, use soap and hot water and always wear change as well.
gloves, and a breathing mask, if necessary. For 9. At the end of two weeks, discuss what
more information about mold and health concerns happened to the apple and bread. What
about mold, visit http://www.epa.gov/mold. changes were observed?

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Wrap Up school?
Review questions & discussion: Mold needs moisture and a food source
Did mold grow on the apple or bread first? to grow. The best way to reduce and
Mold tends to grow on the bread first. prevent mold growth and home and in
How long did it take to see mold growth? school is to control moisture. Keep
Answers may vary based on moisture and humidity levels at home and in school
temperature of the classroom. By the end of low with ventilation systems or a
the first week, mold growth should be visible. dehumidifier that remove excess
What does the mold look like? moisture from the air. It is also
Mold growth may vary in color, but tends to important to repaid leaks and remove
be white fuzzy spots that grow larger. existing mold growth with soap and hot
What color is the mold? water.
Mold will vary in color from white to green,
blue, or grey. Assessment:
Texture: Is the mold fuzzy, lumpy, flat, shaped? Assess students based on their performance in
Texture is likely to be fuzzy and bumpy, but the activity. Each student should have
will vary. completed a worksheet with sketches and
Does the mold spread from one object to the observations of their experiment. Use the wrap-
other? up questions to evaluate the student knowledge
Once mold growth is established, it will gained in this activity.
spread to other objects in the bag.
Do you notice different molds on different foods? Extensions:
Mold growth will vary on food items used, 1. The mold growth experiment can be
location, and temperature. extended for a longer growth cycle.
Why is it important that we not open the bags to 2. Repeat the experiment, but cover the plates
smell the mold? so that students can compare mold growth in
It is very important that the bags stay sealed t light and dark environments.
o prevent allergic reactions and the spread of 3. The experiment can also include the use of a
mold spores into the air. Once mold growth variety of foods to compare different types,.
is established in the bags, mold will start to Colors, and shapes of mold growth.
release spores. When breathed in, mold and 4. Instead of using individual disposable bags
mold spores can trigger allergic reactions and plates, the classroom can conduct a
and irritations for people who are sensitive to mold experiment using one large glass jar or
them. Make sure to discard sealed that can be tightly sealed. Please be careful
experiment bags at the end of the experiment not to open the mold filled container inside
in the garbage. buildings. If the container is to be reused,
Are there different types of mold? Are some more open it outside, away from children and
harmful than others? dispose of the moldy contents in the garbage
There are thousands of species of mold. or a compost container. To thoroughly wash
While all molds have the potential to cause the jar, use soap and hot water.
health effects, not all molds are toxic. Some
molds have beneficial uses to create things
like cheeses and medicines. The research Resources and Related Links:
on molds that produce harmful toxins, called U.S. Environmental Protection Agency:
mycotoxins, is on-going. Mold growth in a www.epa.gov/mold/
building does not always indicate the U.S. Environmental Protection Agency:
presence of toxic molds, but for health and Learn the Issues: Air
safety, mold should be removed right away. www.epa.gov/mold/moldguide.html
What does mold need to grow and how can you www.epa.gov/mold/pdfs/moldguide.pdf
help prevent the growth of mold at home and in Centers for Disease Control and Prevention
www.cdc.gov/mold/
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Student Mold Growth Observation Worksheet: Name: __________________________
Instructions:
1. DO NOT open your experiment bag.
2. Look at the bread and apple on the plate in your experiment bag. What do you see?
3. Answer the observation questions to record your data and then draw a picture of what
you see in the space provided beneath the questions.

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________ Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

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 Name: _______________________________

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

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 Name: _______________________________

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Day ______ Data and Observations: Is mold growing?__________ What is mold growing on?________________
What color is the mold?__________________Describe the texture of the mold (fuzzy, smooth, lumpy):
______________________________________________________________________________________________
Draw a picture of your experiment: What do you see?

Final Observations:
What changes did you observe from start to finish? ___________________________________________________
What happened to the bread and apple in your bag? __________________________________________________
How can you use this new knowledge to help prevent mold growth at home or in school? ____________________
_______________________________________________________________________________________________
What does mold need to grow?_____________________________________________________________________