Every Drop Counts – A Study of Cycles – Grade Seven
Ohio Standards Lesson Summary:
Connection: This lesson teaches students about natural cycles. They will
Earth and Space Sciences
explain that cycles move resources among different sectors
of the environment. Students will complete an activity
Benchmark C following the pre-assessment that demonstrates the linkages
Describe interactions of in a cycle. Students will refer back to this activity as they
matter and energy study the water cycle in laboratory activities. The water
throughout the lithosphere,
hydrosphere, and
cycle demonstrates the movement of material between the
atmosphere (e.g., water lithosphere (land), hydrosphere (water) and atmosphere
cycle, weather and (air).
pollution).
Estimated Duration: Five hours
Indicator 1
Explain the
biogeochemical cycles
which move materials
between the lithosphere Commentary:
(land), hydrosphere (water) Biogeochemical cycles are conceptually abstract because
and atmosphere (air).
many parts of the cycles are invisible to the naked eye. This
Indicator 3 lesson helps students learn about the water cycle by
Describe the water cycle incorporating inquiry methods and hands-on activities. For
and explain the transfer of example, students model cycles by tossing balls in
energy between the repeatable patterns within a circle. Students also observe
atmosphere and
hydrosphere.
how plants move water from a test tube into a plastic bag
wrapped around its leaves via transpiration.
Pre-Assessment:
Pass out copies of Attachment A, Where is the Water?
Have students will complete the attachment.
Scoring Guidelines:
Use Attachment B, Where is the Water, Possible Answers, to
assess student understanding.
Post-Assessment:
Copy and distribute Attachment C, The Water Cycle.
Have students complete the attachment for their
assessment.
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Every Drop Counts – A Study of Cycles – Grade Seven
Scoring Guidelines:
See Attachment D, The Water Cycle Answers, to assess student responses.
Instructional Procedures:
Day One
1. Have students complete the pre-assessment.
2. Have students stand and form a circle.
3. Hand one student a sponge ball. Tell this student to pick out another student across from
them in the circle and prepare to throw the ball to them. Have the student say the
recipient's name and toss them the ball. Remind them that they must remember who
threw them the ball and to whom they threw the ball.
4. Instruct the second student to name a different student across the circle and toss the ball
to him or her.
5. Have students continue this process until all student names have been called. Tell the last
student to toss the ball to the person that began the exercise.
6. Have the group continue this activity and then introduce another ball and another ball
until you have three balls moving about the circle at different places.
7. Remove a student from the circle and tell students to observe the results.
8. Instruct students to use their science journals to reflect on the pre-assessment and activity
by recording responses to the following questions:
Today, what did you learn that helps you understand the concept of cycles?
What questions would you like to have discussed while we talk about cycles?
Day Two
9. Conduct an introduction to the topic of the water cycle. Your introduction should:
Discuss the ball-tossing exercise from Day 1. Students should use the analogy to
understand that cycles move resources in predictable pathways.
Present the water cycle in a visual manner.
Discuss the various stages of the water cycle. Make sure to explain that evaporation
moves only water vapor into the atmosphere, leaving any dissolved particulates
behind.
Generate a list of vocabulary words for definition (see the Vocabulary section of this
lesson).
10. Set out materials for students to use in a laboratory setting, including beakers, salt, water,
a heat source and a balance.
11. To help students visualize evaporation, first have students weigh their beaker and record
the mass in their journals.
12. Have students weigh 10 g of NaCl and add it to their beakers.
13. Have students add 50 mL of water to each beaker.
14. Have students place their beakers on heat sources and boil until all the water is gone.
15. Instruct students to weigh their beakers and record this mass in their journals.
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Every Drop Counts – A Study of Cycles – Grade Seven
Instructional Tip
Use any type of salt for this activity. The difference between the two mass readings should
be approximately 10 g. This represents the salt removed from the water that was evaporated.
16. Have students compare the original mass of their beakers to the final mass of the beakers,
and record this difference in their journals and on the board.
17. Have students record the data from other groups in their journal.
18. Have students reflect on the following questions in their journals:
Why does the beaker have a different weight than when you began this exercise?
Base your answer on the data generated by your class.
Why would this process be important to the movement of materials from the
hydrosphere to the lithosphere?
19. Instruct students to use their textbook, a resource book or notes that have been generated
in class to define the terms in the Vocabulary section of this lesson. Pictures or diagrams
could also be drawn in addition to written definitions to help visual learners.
Day Three
20. Collect several “weeds” with long stems. Be sure to keep the roots intact. Save in water
for use by students in the laboratory. Prepare rubber stoppers by making a cut all the way
through the stopper from the center hole to the edge. This will produce a slot into which
plant stems can be inserted. When the stopper is inserted in a test tube it will hold a plant
in place with the roots just reaching the bottom.
21. To help students observe transpiration, first have them place 30 ml of water into a large
test tube.
22. Tell students to secure a plant from the collection into a cut stopper so that the roots are
just at the bottom of the test tube.
23. Have the students mark the height of the water on the outside of the test tube.
24. Tell the students to next weigh a small plastic bag with a penny in it. (The penny helps
the water to collect in one part of the bag. This allows students to see more easily the
production of water that has condensed after it transpired.) Then, using a twist tie, tell
them to carefully cover the leaves with the bag.
25. Have the students place their plants in a sunny place or under a sun lamp.
26. Once the students have completed the preparation of the plant for measuring its
transpiration capability, lead a class discussion that challenges students to make
predictions about the expected results.
27. Have students reflect on the laboratory as they answer the following questions in their
journals:
What predictions did your class make about the expected results on your laboratory?
Do you agree with these? If so, why? If not, why not?
28. Pass out Attachment E, Not a Drop to Lose, to students. Tell students that for homework,
they will define the vocabulary words and then make game cards following the directions
on the handout.
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Every Drop Counts – A Study of Cycles – Grade Seven
Day Four
29. Returning to the test tubes from Day 3, have students obtain their test tubes from the
lighted location and mark the height of the water on the outside of the test tube. Instruct
students to measure the difference between the original water height and the new water
height in the test tube.
30. Instruct students to carefully remove the plastic bag with the penny from the plant.
31. Have students weigh the bag and calculate the amount of water that has transpired in 24
hours.
32. In small groups, have students return to their previous entries about their predictions for
the transpiration exercise. Have them discuss the results and their relationship to the
predictions that they made the day before. Have them reflect on the significance that the
process of transpiration has on the water cycle, and record this in their journal.
33. Have students play the game Not a Drop to Lose, following the directions on Attachment
F, Not a Drop to Lose Directions. During the game, make sure that students focus on
learning the meaning of the different vocabulary words used in this lesson.
Day Five
34. Proceed to the Post-Assessment.
Differentiated Instructional Support:
Instruction is differentiated according to learner needs, to help all learners either meet the
intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the
specified indicator(s).
Have students working beyond the indicator contrast the water cycle to other
biogeochemical cycles on Earth.
Have students working toward the indicator create a collage using pictures from a
magazine showing different parts of the water cycle, linking them together with arrows
and vocabulary words.
Extensions:
Have students research water usage and generate a table that identifies normal daily tasks
and the amount that is used for the each. Using this information, have the students
generate a weekly water usage chart for themselves.
Have students make a “cloud” chamber. The basic procedure is: Pour hot boiling water
on the bottom of a 1L plastic bottle. Cap the bottle. Drape a bag of ice over the top of the
bottle. Let it stand for several minutes. Squeeze the side of the bottle and a cloud will
appear.
Homework Options and Home Connections:
Have students keep a journal of water usage per day for each member of the family.
Instruct them to draw a data table and make a graph of the information collected. Write
suggestions you have for conserving water in your home. Discuss these with your parents
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Every Drop Counts – A Study of Cycles – Grade Seven
and create a plan that you can follow. Share these with the class on a water conservation
bulletin board.
Have students do a simple laboratory in the kitchen that shows condensation,
precipitation, and evaporation. Brief instructions for these laboratories are:
Condensation: Place ice cubes into a dry glass. Observe the outside of the glass for 10
minutes. Record what happens. (The water vapor in the warm room air comes into
contact with the cold glass. Water vapor condenses on the outside of the glass.)
Evaporation, Condensation, Precipitation: Place a measured amount of water in a pan
and bring it to boil. Boil it for 10 minutes. Observe. Carefully take a glass dinner
plate and hold it over the boiling water for 15 seconds. Remove it and observe. Hold
it over the water for one minute. Observe. Let the water cool and measure its volume.
(The water vapor from the boiling water comes in contact with the cold plate and
condenses. Once this becomes too heavy, the plate “rains.”)
Materials and Resources:
The inclusion of a specific resource in any lesson formulated by the Ohio Department of
Education should not be interpreted as an endorsement of that particular resource, or any of
its contents, by the Ohio Department of Education. The Ohio Department of Education does
not endorse any particular resource. The Web addresses listed are for a given site’s main
page, therefore, it may be necessary to search within that site to find the specific information
required for a given lesson. Please note that information published on the Internet changes
over time, therefore the links provided may no longer contain the specific information related
to a given lesson. Teachers are advised to preview all sites before using them with students.
For the teacher: Sponge balls, note cards, beaker, graduated cylinder, salt (NaCl), heating
device, triple-beam balance, test tubes that can hold 25 mL, single-hole
stopper to fit the test tube, weeds with root system, plastic bag with twist
tie, pennies to weight corner of plastic bag, ring stand with test tube clamp,
attachments.
For the students: Sponge balls, note cards, beaker, graduated cylinder, salt (NaCl), heating
device, triple-beam balance, test tubes that can hold 25 mL, single-hole
stopper to fit the test tube, weeds with root system, plastic bag with twist
tie, pennies to weight corner of plastic bag, ring stand with test tube clamp,
attachments.
Vocabulary:
atmosphere
condensation
cycle
evaporation
hydrosphere
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Every Drop Counts – A Study of Cycles – Grade Seven
lithosphere
precipitation
transpiration
water cycle
water vapor
Technology Connections:
Have students use graphing calculators to compare transpiration rates of plants under
various light intensities.
The website for the U.S. Geological Survey, at www.water.usgs.gov, covers a variety of
issues related to water quality and the water cycle.
Research Connections:
Marzano, R. et al. Classroom Instruction that Works: Research-Based Strategies for
Increasing Student Achievement. Alexandria: Association for Supervision and Curriculum
Development, 2001.
Summarizing and note taking are two of the most powerful skills to help students
identify and understand the most important aspects of what they are learning.
Homework and practice provide students with opportunities to deepen their
understanding and skills related to content hat has been presented to them.
Generating and testing hypotheses engages students in one of the most powerful and
analytic of cognitive operations. It deepens students’ knowledge and understanding. Any
of the following structured tasks can guide students through this process:
Systems analysis;
Problem solving;
Historical investigation;
Invention;
Experimental inquiry;
Decision making.
General Tips:
Students should keep a journal of their activities in science. They should date each entry
and begin it with the objective. New information, discussion questions, laboratory
procedures and data are important parts of this journal.
Attachments:
Attachment A, Where is the Water?
Attachment B, Where is the Water, Possible Answers
Attachment C, The Water Cycle
Attachment D, The Water Cycle Answers
Attachment E, Not a Drop to Lose
Attachment F, Not a Drop to Lose Directions
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment A
Where is the Water?
Name:_____________________
1. Cycles are a part of the world around you. Draw the shape that you think best represents
a cycle.
2. Why did you choose this shape?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
3. Draw a picture of the water cycle. Make sure that you label all the parts and give a brief
description of what is happening.
4. How well do you understand the following concepts? Rate your understanding of each
word as a 1, 2, 3, or 4. A 1 means you are not familiar with the word/concept and a 4
means you could teach the word/concept to your friend. For any concept you have a 3 or
4, define them on the back.
cycle 1 2 3 4 water cycle 1 2 3 4 water vapor 1 2 3 4
hydrosphere 1 2 3 4 lithosphere 1 2 3 4 atmosphere 1 2 3 4
precipitation 1 2 3 4 evaporation 1 2 3 4 transpiration 1 2 3 4
condensation 1 2 3 4
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment B
Where is the Water, Possible Answers
Name:____________________________
1. Cycles are a part of the world around you. Draw the shape that you think best represents
a cycle.
Circle
2. Why did you choose this shape?
A cycle is a continuous process through which something moves in nature. It has no
beginning and no end. Therefore, a circle which has no beginning and no end is a good
shape to choose.
3. Using the water cycle as an example of a cycle in nature, draw a picture of the water
cycle. Make sure that you label all the parts and give a brief description of what is
happening.
* required
*Evaporation: Most over oceans but also over lakes and rivers.
Transpiration: Release of water by plants into the air. Water Vapor
*Condensation: As the water vapor cools, it forms clouds.
*Precipitation: When the water droplets become heavy enough that they fall back to the
Earth. lakes, rivers, oceans, runoff and groundwater
4. How well do you understand the following concepts? Rate your understanding of each
word as a 1, 2, 3, or 4. A 1 means you are not familiar with the word/concept and a 4
means you could teach the word/concept to your friend.
cycle 1 2 3 4 water cycle 1 2 3 4 water vapor 1 2 3 4
hydrosphere 1 2 3 4 lithosphere 1 2 3 4 atmosphere 1 2 3 4
precipitation 1 2 3 4 evaporation 1 2 3 4 transpiration 1 2 3 4
condensation 1 2 3 4
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment C
The Water Cycle
Name ____________________________
1. A circle is used to generally describe the concept of cycles. Why is this shape an
appropriate one to use? Why is this shape not a true representation of cycles in nature?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
2. Describe the general path of water as it moves through the water cycle. (You may draw
and label pictures or use words.)
3. What causes the movement of water? In your description above, show the energy source
that drives this cycle.
4. List three places from which water evaporates.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
5. How can the water cycle renew Earth’s supply of fresh water?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment C (continued)
The Water Cycle
6. Explain how water moves using the terms hydrosphere, lithosphere, and atmosphere.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
7. In the pre-assessment your completed the following data on your understanding of the
concepts of the lesson. Complete it again.
Rate your understanding of each word as a 1, 2, 3, or 4. A 1 means you are not familiar
with the word/concept and a 4 means you could teach the word/concept to your friend.
cycle 1 2 3 4 water cycle 1 2 3 4 water vapor 1 2 3 4
hydrosphere 1 2 3 4 lithosphere 1 2 3 4 atmosphere 1 2 3 4
precipitation 1 2 3 4 evaporation 1 2 3 4 transpiration 1 2 3 4
condensation 1 2 3 4
Compare these evaluations to what you had at the start of the lessons. How well do you
understand the following concepts NOW? Discuss this briefly.
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment D
The Water Cycle Answers
1. A circle is used to generally describe the concept of cycles. Why is this shape an
appropriate one to use? Why is this shape not a true representation of cycles in nature?
A circle is appropriate because materials in a cycle eventually return to their point of
origin. The shape is not a true representation however, because materials will not always
progress smoothly to the next step in a cycle. Sometimes steps are skipped. and sometimes
some materials remain in a step while others move on.
2. Describe the general path of water as it moves through the water cycle. (You may draw
and label pictures or use words.)
Water moves from a surface source, to the air, and back again to the ground. The water
may seep through the ground until it reaches the surface source again. There are many
intervening variables in the route, such as plants, oceans, rivers, precipitation, and
evaporation rates.
If a picture is used, it should show the cycle returning to its point of origin.
3. What causes the movement of water? In your description above, show the energy source
that drives this cycle.
The movement of water is ultimately caused by the sun. The heat of the sun causes
differential heating of surface water, which causes currents. The sun also drives
evaporation and transpiration.
The sun should be drawn in question 2.
4. List three places from which water evaporates.
The list can include streams, rivers, ponds, lakes, oceans, land surface after precipitation,
and even the bodies of animals. This list is not exhaustive, and the students may supply
other examples.
5. How can the water cycle renew Earth’s supply of fresh water?
Water vapor in the air condenses and falls back to Earth. Water that is used by human
consumption is eventually replenished as the water flows into reservoirs, rivers, and
underground aquifers.
6. Explain how water moves using the terms hydrosphere, lithosphere, and atmosphere.
Evaporation moves water from bodies such as lakes and oceans into the atmosphere.
Evaporation and transpiration move water from the liquid state in the lithosphere into the
vapor phase. Vapor in the atmosphere condenses and returns as liquid to the lithosphere
and hydrosphere.
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment D (continued)
The Water Cycle Answers
7. In the pre-assessment your completed the following data on your understanding of the
concepts of the lesson. Complete it again.
Rate your understanding of each word as a 1, 2, 3, or 4. A 1 means you are not familiar
with the word/concept and a 4 means you could teach the word/concept to your friend.
cycle 1 2 3 4 water cycle 1 2 3 4 water vapor 1 2 3 4
hydrosphere 1 2 3 4 lithosphere 1 2 3 4 atmosphere 1 2 3 4
precipitation 1 2 3 4 evaporation 1 2 3 4 transpiration 1 2 3 4
condensation 1 2 3 4
Compare these evaluations to what you had at the start of the lessons. How well do you
understand the following concepts NOW? Discuss this briefly.
This is a gauge to help students reflect on their learning. There are no correct or incorrect
answers.
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment E
Not a Drop to Lose
Vocabulary Words
Use resources to obtain the definitions for the following vocabulary words and then use these
definitions to make game cards.
1. Cycle –
2. Water cycle –
3. Water vapor –
4. Precipitation –
5. Evaporation –
6. Transpiration –
7. Condensation –
8. Hydrosphere –
9. Lithosphere –
10. Atmosphere –
11. Ocean currents –
12. Clouds –
13. Groundwater –
14. Runoff –
15. Solar energy –
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment E (continued)
Not a Drop to Lose
Making the cards:
Make 15 cards similar to the ones below that use all of the vocabulary words and their
definitions. A card cannot have the vocabulary word and its definition on the same card.
I have a continuous I have what happens when I have what happens when
process by which matter water vapor cools forming water droplets become
moves through the living clouds. heavy enough and fall
and nonliving parts of the back to the earth.
environment.
Precipitation Cycle Condensation
1 2 3
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Every Drop Counts – A Study of Cycles – Grade Seven
Attachment F
Not a Drop to Lose Directions
Playing the Game:
1. Divide the students into groups of three or five.
2. Shuffle the cards and give each student group an equal number of cards, so that each
student has one card.
3. Have the first student read the definition from his or her card.
4. Have the student who has the word that was just defined says the word. That student
reads the definition from his or her card.
5. When a card has been used, it is placed on the table and cannot be used again.
6. Have students continue the reading of definitions and matching words until all cards have
been used.
7. Students will know that they are correct if they complete the cycle by coming back to the
first student. If the cycle does not come back to the first student, then this means that at
least one student has mismatched a vocabulary word with the wrong definition. The
students must then try to figure out which words were mismatched. They may do this by
playing the game again or discussing the definitions in the group.
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