Names: ______________________________________________________________________________
Polluted Soil Experiment
For this experiment your group will need:
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5 potting cups
Bag of grass seeds
¼ cup measuring cup
Water
Ruler
Mixing stick
Potting soil
Pollutants: Dish soap, salt, vinegar,
and one more that your group would like to use
Essential Questions to Consider Throughout Experiment:
Which soil is better for plant growth?
What effect does pollution have on plants?
How do humans change the planet?
What things might harm soil?
Pollution can work its way into the soil outside. It is your job to investigate how soil pollution
affects plant growth by experimenting with grass seeds and soil pollutants. You will compare the
polluted cups to the one cup that is not polluted to see if there are any differences in plant
growth.
Step 1: On a new page in your research journal, write the title at the top “Polluted Soil
Experiment.” Underneath your title, create a hypothesis for what will happen in this experiment.
Example: If grass seeds are planted in soil and in polluted soil, then…
Step 2: Label your five potting cups 1-5. Write down in your research journal a list like this:
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Cup #1
Cup #2
Cup #3
Cup #4
Cup #5
Names: ______________________________________________________________________________
Step 3: Fill Cup #1 ¾ full with potting soil. Write in your journal next to Cup #1 “Potting soil.”
Step 4: Fill Cup #2 ¾ full with potting soil. Add ¼ cup of dish soap to cup and use mixing stick
to mix soap with soil. Write in your journal next to Cup #2 “Potting soil and dish soap.”
Step 5: Fill Cup #3 ¾ full with potting soil. Add ¼ cup of salt to cup and use mixing stick to mix
soap with soil. Write in your journal next to Cup #3 “Potting soil and salt.”
Step 6: Fill Cup #4 ¾ full with potting soil. Add ¼ cup of vinegar to cup and use mixing stick to
mix soap with soil. Write in your journal next to Cup #4 “Potting soil and vinegar.”
Step 7: Fill Cup #5 ¾ full with potting soil. Add ¼ cup of the pollutant that your group chose to
cup and use mixing stick to mix pollutant with soil. Write in your journal next to Cup #5
“Potting soil and ___________.”
Step 8: Scatter grass seeds across the top of the soil evenly in all five cups.
Step 9: Place all cups in sunlight.
Step 10: Water each cup with ¼ cup of water and repeat this every other day for 10 days.
You will be observing your grass growth over 10 days total. You need about 4-5 pages in your
journal for this entire experiment, so you can paperclip them together for now and do other WBI
activities after the paperclipped section of your journal.
For each day (Days 1-10) you should draw the following diagram in your journal:
Day # _____
1
2
cm
4
3
cm
cm
5
cm
cm
Names: ______________________________________________________________________________
Each day when you look at your potting cups and draw the diagram in your research notebook,
you should draw what you see. Then, measure the height of the grass (in centimeters (cm)) from
the soil level up to the top of the blade of grass. Write this measurement under each cup in your
notebook.
***Remember to water your grass every other day!! (Days #1, 3, 5, 7, and 9)***
After you have recorded your picture and heights for Day #10, draw the following diagram into
your research notebook and record all of your grass heights from Days #1-10 in the diagram.
Day 1
Day 2
Day 3
Day 4
Day 5
Day 6
Day 7
Day 8
Day 9
Day 10
Cup #1
______ cm
Cup #2
_______ cm
Cup #3
______ cm
Cup #4
______ cm
Cup #5
______ cm
As a group you should think about the results that you got for this experiment. Think about
possible answers to the essential questions from the beginning of this experiment and write these
in your research journals. Each answer must be at least 3 sentences long.
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Which soil is better for plant growth?
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What effect does pollution have on plants?
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How do humans change the planet?
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What things might harm soil?
Lastly, with your group think of ways that humans can reduce the amount of soil pollution in the
world. After your answers to the questions in your research journal, create a brainstorming list of
ways to reduce soil pollution in the world.