Fellow name: Sara Painter
Title of Lesson: What is in our water?
School: Culver City Middle School
Grade Level: 7th
Subject(s): Life Science
Summary
This lesson is designed to teach students the importance of anthropogenic effects on local
water systems and the potential impacts on living things. The students will learn about
human water use, natural verses urban watersheds and the Ballona Creek watershed, with
an emphasis on human impact on water quality. The students will test the water quality of
three natural sources and several artificial sources. The natural sources will need to be
collected from the UCLA creek, Ballona creek directly behind Culver City Middle School
(CCMS) and from the tap. The artificial waters will need to be made up to contain one or
more point source pollutants that often get into the city storm drains, such as bleach,
fertilizer, soda and sea salt.
After the students test the waters and have a chance to think about how the various
chemicals they found may affect living things they will conduct an experiment to test how
water quality will affect the growth of plants. Students will work in small groups to
germinate pea plants using four different water treatments. All the students will use
filtered water as a control and choose three other waters to test. After 10-17 days the
students will collect data on their pea seeds making note of the number of seed that
germinate and survive. They will also be measuring the shoot height and counted the
number of leaves on all germinated plants.
The students will use their results from this experiment along with the knowledge they
gained from the water testing activity to make some conclusions about how water quality
affects living things.
In what way is your lesson/activity inquiry-based?
This lesson is inquiry based because the students will complete a science experiment. They
will start by making observations about various waters while completing their water
testing activity. They will use the knowledge gained here as well as the information
presented to them about water cycles and watersheds to make a hypothesis about how
several waters that they chose will affect the germination and growth of pea seeds. The
students then set up the experiment and collect data to test their hypothesis. After
completion of the experiment the students gather data on their pea seeds and use the
information to make a bar graph to illustrate the data and come up with several
conclusions related to the original experimental question.
Time Required
Day 1:
-
Lecture - Human water use, natural verse urban watersheds, water pollution~
30 min
Water testing activity – Students work as a class to test several chemicals in 8
different water sources ~ 40 min.
What’s in our Water worksheet - Students start the worksheet in class and finish
as homework. ~30min
Day 2:
-
Review of water testing activity results ~ 10 min
Experiment Introduction and set up demo ~ 10 min
Experiment set up - Students use the experiment set up hand out to choose their
treatment waters, make a hypothesis and set up their pea plant experiment ~ 30
min
Experiment 10-17 days (depending on classroom light conditions)
- Students may find it interesting or useful to make some observations on their
experimental pea seeds every few days.
Day 3 - Data collection instructions and demo ~ 15 min
- Data collection - students collect data regarding the germination, survival,
average shoot growth and average number of leaves on their experimental
plants. ~ 30 min
- Interpreting Results and drawing conclusions worksheet – students begin in
class and finish as homework ~ 20 min
Group Size
Each class will be divided into 8 groups. (2-5 students depending on class size)
Cost to implement
Zip lock bags ~$10
Clear tape ~ $8
Sharpies ~ $ 10
8 x 1 gallon water containers ~$15
64 x 12 once water bottles ~ $15
Pea seeds ~$20
Water quality testing kit (at least 40 tests of each chemical):
Lamotte AM-12 Testab Kit (5849)
http://www.lamotte.com/pages/edu/5849.html
Total: $60
Learning Objectives
After this lesson, students should be able to:
-
Describe how much water they use in their day to day lives
Explain why water conservation and water pollution is an important issue
List several chemicals or pollutants that may enter our local waterways
Describe whether a chemical may be harmful or beneficial to plants
Make a hypothesis based on previous knowledge and observations
Describe how to set up an experiment to test water quality effects on plants
Use data to construct a bar graph
Draw conclusions from experimental data
Introduction / Motivation:
Day 1:
Begin this lesson with a lecture/presentation on natural verses urban watersheds, and
water pollution. The Powerpoint presentation will begin with a “quiz” to grab the students
attention an interest. The quiz will ask the students to think about how much water they
use in their day to day lives and where their local water supply comes from. The students
will be shocked to discover not only how much water they use to take a shower but also
how much water is needed in agriculture to produce vegetables and meats.
Following the introduction present the information regarding the difference between
natural and urban watersheds emphasizing that water runoff is an important issue in
urban places. Next introduce the students to the Ballona watershed. The Powerpoint
presentation includes several pictures of the Ballona creek watershed and the trash and
other pollutants in the water. Ask the students what they think might be in the water and
how that might affect the organisms living in the area.
Lastly, introduce the students to some of the common chemicals or elements in the water
that they will be testing during the lab activity. Explain the sources of these chemicals and
discuss their effects on biology. Hand out the water data table to the students and provide
a demo for how to use the water testing kits. Ask the students to think about what
chemicals they find in the different waters they test.
Day 2:
Before introducing the students to the pea plant experiment review the water testing
results from the previous day. Ask the students which water they thought was the most
polluted and why. Review which chemicals are known to have positive and/or negative
effects on plant growth. Ask the students which waters that they tested had these
chemicals. Ask the students to hypothesize which waters might result in the best or worst
plant growth.
Following the review introduce the students to the experiment that they are going to be
conducting over the next several days. Start the discussion with a review of the scientific
method (which the students should have previously learned). Emphasize that the students
will be doing most of the steps including observation, hypothesis, data collection,
conclusions and communication. They only part being provided to them is the
experimental question. Pass out the “How does water quality impact living things”
worksheet, give a demo of how to set up the pea plant experiment and explain what data
the students will be collecting at the end. Ask the students to head to the lab stations and
start by choosing the 3 waters they’d like to test and then make a hypothesis. After their
hypothesis has been approved give them the supplies to start setting up their pea plant
experiment.
Day 3:
Today you will have the students collect the data on their pea seeds. Start by
reviewing/reminding them of the initial experimental question and have them review the
hypothesis they made before setting up the experiment.
Procedure
Day 1:
Following the lecture/presentation the class of students will be divided into 8 groups. This
can be done by simply handing out the “what’s in the water?” data tables which have the
group number written on the top. The students will stay in these groups for the remainder
of the lesson including the pea plant experiment set up and data collection. Each group of
students will be testing 4 different waters for 2 different chemicals (a total of 8 tests). They
will need to refer to their water testing data table to identify which waters and tests they
should complete. The data from the entire class will be compiled on the white board and
each student will be able to copy down the information required to complete their table.
The students will then be given the “what’s in the water?” worksheet to complete. The first
half of worksheet will be completed in class as part of a group discussion. The students will
need to complete the second half of the worksheet as homework using their lab data and
the “Chemical Information Table” which will be provided at the beginning of the lab.
Day 2:
Pass out the “How does water quality impact living things” worksheet, give a demo of how
to set up the pea plant experiment and explain the data to be collected at the end. The
worksheet will provide the students with the experimental question: “How does water
quality effect growth of plants?” It also includes a list of attributes that they will be
measuring at the conclusion of the experiment: the number of seeds that germinate,
survival of plants that germinate height of each plant, and the number of leaves on each
plant.
Ask the students to head to the lab stations and start by choosing the 3 waters they’d like to
test, in addition to the control and then make a hypothesis about how they think the waters
they chose will affect pea seed germination and growth. After their hypothesis has been
approved by you or the teacher give them the supplies to start setting up their pea plant
experiment following the directions on the water quality experiment set up instructions.
Day 3:
At the conclusion of the experiment the students will take the finial measurements on their
experimental plants. The students will fill out the “experiment data collection” tables
provided. The students will also calculate the average number of leaves and the average
height of the plants in each treatment. After the students finish collecting their data they
will return to their seats where they will begin working on the “interpreting results and
drawing conclusions” worksheet which they will finish as homework.
Materials List
Each group will need:
For the water testing activity (day 1):
 Appropriate test kit

One 16once water bottle for each of the 8 waters

What’s in the water data collection table (1 per student)

Chemical information table (1 per student)

What’s in the water worksheet (1 per student)
For the experiment set up (day 2):

How does water quality affect living things worksheet (1 per student)

One 16once water bottle for each of the 8 waters

4 paper towels

4 clear zip lock bags

24 pea seeds

One sharpie pen

Clear tape (four 1 foot strips)

Masking tape (one 4 inch strip)
Data collection (day 3):

Experiment data collection worksheet (1 per student)

Interpreting results and drawing conclusions worksheet (1 per student)

4 rulers

calculator
To share with the entire class:

Safety Issues:
1 gallon container filled with each of the 8 water treatments (extra supply)
Creek water may contain harmful bacteria. Instruct the students to wash their hands after
handling the water and of course not to drink the water.
Lesson Closure:
A closing discussion would be most appropriate on the day the Results and Conclusions
worksheets are being collected. By this point the students should have had some time to
think a little more deeply about the data they collected. Ask the students which of their
four waters resulted in the best growth of pea seeds and how they determined this answer.
Ask the students why they think this water may have resulted in better growth than the
others. Ask the students to refer back to their original hypothesis and to explain if the data
they collected supported their hypothesis or not.
Once you have reviewed with the students their experimental results bring the discussion
back to the initial concepts introduced in this lesson. Ask the students to think back to the
initial introduction to the Ballona water shed and urban water cycles. Ask the students
what effects they would expect to see if one or more of their experimental waters were
haphazardly discarded into the city storm drain system.
Is this lesson based upon or modified from existing materials? If yes, please specify
source(s) and explain how related:
n/a
References:
Bruton, Sheila and Feye Ong. Science Content Standards for California Public Schools.
Sacramento, CA: California Department of Education, 2000
Illinois Department of public Health – Environmental Health
http://www.idph.state.il.us/envhealth/factsheets/ironFS.htm
La Motte Test Tab Water Investigation Kit Instructions
T. Hougue - Power Point Presentation: Watersheds, Summer Institute 2009
Attachments:
Attached handout document contains the following:
- What is in our water?
- Chemical Information Table
- How does water quality impact living things?
- Experiment data Collection tables
List CA Science Standards addressed:
7c: Communicate the logical connection among hypotheses, science concepts, tests conducted,
data collected, and conclusions drawn from the scientific evidence.
7e: Communicate the steps and results from an investigation in written reports and oral
presentations.