UP, UP, AND AWAY!
Lesson Two
Overview
Setting the Stage:
Water is a substance that can be found
in three forms: a liquid, a solid, and a
gas. Water can be found most often in
its liquid form and becomes a solid
when the temperature drops below
freezing 32° F or 0° C. Water becomes
a gas when the temperature rises to
212 F or 100 C and it escapes into the
air. Evaporation is the process which
turns liquid water into a gas. The more
heat that is applied to water, the faster
the process of evaporation takes place.
Water is in a constant cycle of
changing from a liquid to a gas
because it is made up of millions of
molecules that are in constant motion.
At the conclusion of this section, your
students should be able to understand
the process of evaporation.
1. Begin by explaining to the students that water can be found in
three forms: solid, liquid, and gas.
2. Show students a glass of water and ask, “What form is water
found here?” (A: liquid)
3. Show students an ice cube and ask, “What form is water found
here?” (A: solid)
4. Explain to the students that water can also be found in a gas
form. Although you cannot see the gas form of water, when heat
energy is applied to water, it turns into gas and rises up into the air.
This is a process called evaporation.
Evaporation- To convert or change water into a vapor with the
application of heat.
Today’s lesson will introduce you to the concept of evaporation and
will demonstrate how it works.
Activity-H2O on the Go
1. Students will create a water cycle model in a closed bag and
observe how water evaporates from the cup.
Objectives
TEKS objectives that will be addressed
in this section include: Science 1.A,B,
2.A,C,D,E, 4.A, 5.B,6.A,7.B
Completion Time
Completed over a three-day period
Materials
2. Pass out a Zip Lock style bag and cup to each student. Place
approximately 2 ounces of water in the cup and mark the water line
with a piece of tape or black marker. Tape the cup to the inside of
the bag to prevent spilling. (See educator page for graphic of this
model).
3. Seal up the bag and then tape it in a warm sunny place
(preferably a window), tilted on an angle so that the sides will slant
down from the top allowing the droplets to slide down and collect in
the bottom of the bag.
(See next page for material list)
4. Pass out Student Observation Sheet (Journal Page #1) and have
students record what happens over a three day period. Ask the
students to begin their observations on the first day by coloring the
water in the bag blue.
Follow-Up
1. Ask students what they think will happen to the water in the cup.
Science
ENGAGEMENT
1.
UP, UP, AND AWAY!
Lesson Two
Materials
1. Glass of water
2. Two or three ice cubes
3. One Zip Lock style bag (quart size
works best-enough for each student)
4. 3.5oz. clear plastic cups (enough for
each student)
5. Masking tape or black marker
6. Watering can filled with water
7. 2 pieces of sidewalk chalk (different
colors)
8. Crayons or colored pencil (same
colors as the sidewalk chalk) for each
student
9. Watch
10. Journal Page #1 (enough for each
student)
11. Journal Page #2 (enough for each
student)
12. Teacher Sheet-Predictions
13. Exploration Backpacks- Hand
towels
Outside Activity: Evaporation Exploration (Preferable to do
in the hottest part of the day and not on a rainy day)
1. Take the hand towels from the Exploration Backpack and soak
them under a faucet until they are completely wet.
2. Take the students outside and have them place the towel in a
sunny location. Note the time. Ask your students to predict how
long it will take for the water to evaporate and dry out the towel.
Note some of the responses on your Teacher Sheet-Predictions.
3. Still outside and with the watering can, pour a small amount of
water on a hard surface (preferably a level sidewalk) creating a
puddle of water.
4. Allow a minute or two for the water to stop running and settle.
With the sidewalk chalk, draw a chalk-line around the puddle. Note
the time on the watch and inform the students of the time. Ask the
students to predict what will happen to the puddle in ten minutes.
5. On their journal page (Journal Page #2), have them record
information about the initial puddle observation. Have them write
the time that the first puddle outline was created. Then ask them to
use a crayon or colored pencil the same color as the sidewalk chalk
outline to draw an illustration of the outline in the box on the right
side of the chart.
6. In ten minutes, come back for another puddle observation. Ask
the students: “Has the puddle changed? How? What happened to
the water?” (A: evaporation)
7. Have the students use a different color chalk to trace the new
outline of the puddle. Then have them record the time and, using a
crayons or colored pencil that matches the color of the new chalk
outline, draw a new illustration of the puddle in their journal. (Note:
Explain that they should try to record the information as accurately
as possible. If the puddle on the sidewalk is smaller, the illustration
on the paper should look smaller, too.)
8. Repeat in ten minute intervals until the puddle has disappeared
2.
UP, UP, AND AWAY!
Lesson Two
9. Have the students look over the information on their journal page, and explain what they noticed about the
observations they have collected. In general, they should notice that over time, the puddle got smaller and smaller,
but basically stayed the same shape. Ask them to consider where the water went.
10. Have the students check their towels over a period of time and note how long it takes for them to dry.
11. Lead a discussion on evaporation. With the sun’s heat, water turns from a liquid to a gas. The water in the
puddle turned into tiny droplets of water called water vapor. It evaporated, and is now in the air. [TEACHER: Please
stress the importance of this point as it will be an important concept in Lesson Three.]
Hero Talk
If you went swimming but forgot to take a towel, how might you be
able to dry off when you got out of the water?
Additional:
1. Get two brown paper towels from the Exploration Backpack. Wet both of the towels and place one in the full
sun outside and one in the shade inside. Have the students compare and contrast the evaporation rates of the
two towels.
3.
UP, UP, AND AWAY!
Lesson Two
WATER CYCLE MODEL
This is what the water cycle model should look like after being put together.
The bag should be tilted at an
angle so that the sides will
slant down from the top
allowing the droplets of water
to slide down and collect in
the bottom of the bag.
4.
UP, UP, AND AWAY!
Lesson Two
PREDICTION SHEET
How long do you think it will take for the wet towel to dry?
Prediction #1: ______________________________
Prediction #2: ______________________________
Prediction #3: ______________________________
Prediction #4: ______________________________
Prediction #5: ______________________________
5.