EXPLORATION
1D. Question: How do bananas, plastic straws, and a napkin
recycle into soil?
1E. In the prediction below, circle the item or items which you
think will recycle into the soil.
Prediction: I think that the
banana
plastic straw
napkin
will recycle into the soil.
1F. Complete the list below with the specific amount of materials
your group will need to use.
Materials for your group:
 3 clear plastic cups
 3 craft sticks
 cm ruler
Graduated Cylinder
 25 ml graduated cylinder
 ____ cm pea gravel
 ____ cm top soil
 ____ cm thick piece of banana
 ____ cm slim plastic straw
 ____ cm x ____ cm piece of napkin
 ______ ml water
Read at the bottom of the curve.
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40
00
35
00
30
00
25
00
20
00
15
00
10
00
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1G. Read the procedures listed below.
Procedure:
1. Measure 2 cm of pea gravel into a clear plastic cup.
2. Measure 4 cm of top soil into the same clear plastic cup.
3. Using a craft stick, dig a small hole in the soil in the cup.
4. Label the craft stick “Banana.” Label the back side of the
craft stick with your group’s number or your name.
5. Measure and cut the banana.
6. Using the craft stick, place the banana in the hole in the
soil. Then cover the banana with soil.
7. In the cup, pour 25 ml of water.
8. Place the unlabeled end of the craft stick into the soil along
the edge of the cup.
9. A different person in your group will repeat steps 1-7 for
the slim plastic straw.
10. A different person in your group will repeat steps 1-7 for
the napkin.
11. Complete 1H, on page 3. Then, make your observations.
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12. Place the cups in a warm, sunny spot.
EXPLANATION
1H. Scientists can only make observations based on facts, not
opinions. Before you make your first set of observations, we are
going to review fact and opinion. Remember that observations
are true statements about what you see. They are not opinions
about what you see. In order to review fact and opinion, let’s
take a look at statements about another type of fruit, the apple.
Read the statements below. Then circle whether that statement
is a fact or an opinion.
Fact
1. The apple is a type of fruit.
Opinion
Fact
2. The apple is pretty.
Opinion
Fact
3. The apple is tiny.
Opinion
Fact
4. The apple in the picture is 2½ cm across.
Opinion
Fact
5. The apple is gross and smelly.
Opinion
Fact
6. The apple has jagged edges where it was
bitten.
7. The apple has a stem.
Opinion
Fact
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Opinion
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Results/Observations:
You are now ready to make your observations (eyes only). You
may choose to use some of the words in the text box below to
help you describe your observations. You may also come up with
other words to use. Record and draw your observations in the
boxes below.
yellow
green
tan
black
clear
soft
mushy
squishy
firm
hard
Banana
dry
damp
moist
soggy
wet
Plastic Straw
smooth edges
flat
bumpy
rough edges
no change
Napkin
First
Observation
Second
Observation
1 week
later
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Banana
Plastic Straw
Napkin
Third
Observation
1 week
later
Fourth
Observation
1 week
later
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EXTENSION/EVALUATION
1I. Using your investigation and the class discussion, complete
the question below.
Scoring Tool
3- Student correctly identified a material which broke down into
soil. Student thoroughly explained what happened to the
material over time using three or four specific details from
their observations and scientific vocabulary.
2- Student correctly identified a material which broke down into
soil. Student thoroughly explained what happened to the
material over time using two specific details from their
observations and scientific vocabulary.
1- Student correctly identified a material which broke down into
soil. Student partially explained what happened to the
material over time using one specific detail from their
observations and scientific vocabulary.
0- Student incorrectly identified a material which broke down
into soil. Student incorrectly explained what happened to the
material over time using no details from their observations or
scientific vocabulary. Incomplete/illegible.
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Summary:
Circle the material you choose to discuss in your summary.
banana
plastic straw
napkin
Describe what happened to the material you chose in the
investigation. Be sure to use specific details from your
observations and vocabulary in your answer.
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