Miami-Dade County Public Schools

Curriculum and Instruction (Science)

Required GRADE 5 ESSENTIAL SCIENCE

Laboratory Activities

QUARTER 2 LABORATORIES

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LAB # 8: AROUND AND AROUND IT GOES! Grade 5 Essential Lab (Teacher’s version)

Adapted from http://myfwc.com/media/150529/CycleInABag.pdf

Benchmarks: SC.5.E.7.1 Create a model to explain the parts of the water cycle. Water can be a gas, a liquid, or a solid and can go back and forth from one state to another. SC.5.E.7.2 Recognize that the ocean is an integral part of the water cycle and is connected to all of Earth's water reservoirs via evaporation and precipitation processes. SC.5.N.1.5 Recognize and explain that authentic scientific investigation frequently does not parallel the steps of "the scientific method." Objective/Purpose:

The student will observe and explain the stages of the water cycle (evaporation, condensation, precipitation) and illustrate that when liquid water evaporates; it turns into a gas (vapor) in the air and condenses as a liquid when cooled, or as a solid if cooled below the freezing point of water.

The student will explain how sunlight and temperature affect the water cycle.

The student will explain why it is important to conserve and protect available drinking water sources.

Background Information: The water cycle is a never-ending cycle that includes evaporation, condensation, and precipitation. The sun is the energy that keeps the cycle moving. The heat energy from the sun changes water into vapor. This invisible vapor then condenses and forms billions of droplets that make up clouds. The moisture from the clouds returns to the earth as rain, snow, or other forms of precipitation. Temperature plays an integral role in this never-ending process by affecting the rate of evaporation and the type of precipitation (e.g., rain, snow, ice). Evaporation is the process in which matter changes from a liquid state to a gaseous state (vapor) Condensation is the process in which matter changes from a gaseous state (vapor) to a liquid state. Condensation occurs as air with water vapor in it cools; clouds are evidence of condensation. Precipitation forms when water droplets in clouds become too heavy to stay in the atmosphere. The water droplets fall in some form, such as snow, ice, or rain, to the earth’s surface. In order for students to understand how the water cycle works, it is important for them to review what they have already learned about water itself, and the different states it can

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assume (solid, liquid, or gas) in our ever-changing environment. This can be done by showing the class three items—a half-filled glass of water, a dish with an ice cube, and a dish with a wet paper towel in the Engage activity in this lab. Teacher Notes: In preparation for this activity, scan your school grounds and locate a hot, sunny wall area where students can mount their mini-water cycle bags. Bags can be affixed to a window facing south inside the classroom if one is available. The bags will need to remain on the wall undisturbed for 3 days. Students will observe the bags over three days. The first phase of the activity in day 1 should begin as early as possible in the school day. The mini-water cycle baggies will need to be checked each morning and afternoon for three days. Add blue food coloring to water before distributing to the groups. Engage: Begin by drawing attention to the glass of water. Ask questions such as:

What is in this glass? What is water? What does it look or feel like? Is water a solid, a liquid, or a gas? Where can you find water? Where does it come from?

Guide the class in establishing that water is a liquid that both falls from the sky in the form of rain and can be found in abundance in oceans, lakes, streams, and underground. Next, pick up the dish with the ice cube and show it to the class.

Ask questions such as these:

What is in this dish? Describe ice. What does it look or feel like? Is ice a solid, a liquid, or a gas? What is ice made of? How is it made? If I left the ice in the room for a few hours, what would happen to it?

Help the class to see that ice is water that has been frozen into a solid because it has been exposed to very low temperatures. Make sure they understand that when ice is allowed to warm up, it returns to liquid water.

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Next, present the dish with the wet paper towel, asking the following questions:

What is this? What would happen if I left it out for a few hours? Why would it dry out? Besides paper towels, what are some other examples of wet things that dry

out over time? (Examples could include wet clothes, watered plants, glasses of water, and puddles.)

What if I put this wet paper towel outside during the winter? What might happen to it? Why?

At this point, students should understand that when water is exposed to warm temperatures, it disappears or evaporates, becoming a gas, while under colder conditions it can freeze into ice, becoming a solid. It is important to emphasize that the three water samples they've seen represent the three states, or forms, that water takes on as temperature and other conditions change.

Explore: Next, divide the class into small groups. To better apply and reinforce what they have learned, have each group create a model of a water cycle. Essential Question: What will happen to water in a cup if the cup is placed inside a sealed bag and left in a warm area? Materials:

Cycle in a Bag” worksheet Quart size zip-lock baggie with writing label 7 oz. clear plastic cup Black permanent marker Measuring cup Water Blue food coloring Masking or duct tape Clipboard or other hard writing surface

Procedures: 1. Introduce and discuss the term “cycle.” Explain to students that in a cycle, a complete

set of events occurs in the same sequence over and over. Ask students to name examples of natural cycles. (Some examples include various plant and animal life cycles).

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Reinforce the idea that both living and non-living things in our environment often undergo cycles. Next, ask students to recall the three major parts of the water cycle (evaporation, condensation, and precipitation). Explain that during this activity students will be working in groups to create their own mini water cycle in a plastic bag, but will keep an individual observation sheet.

3. Divide students into groups of four and distribute a

“Cycle in a Bag” lab sheet to each student in the group. Refer to the diagrams on the worksheet and review and demonstrate the procedure for creating a water cycle in a bag.

Procedures for students:

1. Instruct students to pour 50 mL of water into a small, clear plastic cup and mark the water line in a permanent marker.

2. Have students tape the cup to the inside of the baggie at the lower right corner. Remind students to tightly seal their baggies before beginning the experiment.

3. Remind students to tape their bags on the outside wall at an angle like a diamond and have them write their names at the top of the baggies.

4. If marker flags or flagging tape are available, mark off the wall as designated “study area.”

5. Distribute all materials and assist groups with the preparation of their miniature water cycle models.

Day 1: 1. Distribute a clipboard if available to each group and lead students to the outdoor

study wall site. Have each group securely tape its water cycle bag to the wall. Make sure students tape the bags at eye level so they are easy to observe.

2. Have each student predict what changes will take place inside the bag over the next

three days. Groups should record their predictions on the “Cycle in a Bag” worksheet.

Days 2 and 3 3. Have groups observe their bags daily for three days. Instruct group members to draw

and describe their observations on the “Cycle in a Bag” worksheet.

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Explain/Evaluate: 1. After the third day of observations, ask students to share their observations and

discuss how accurate their predictions were. Conduct a whole-class discussion addressing the following questions:

During what phase of the water cycle is water invisible? (evaporation)

Why is the water invisible during this phase? (because it is a gas)

What causes water to evaporate in the water cycle? ( heat from the sun)

What causes water to condense in the water cycle? (cooler temperatures)

What stage of the water cycle do the water droplets inside the baggie represent? (condensation)

When many droplets of condensed water collect in the atmosphere, what do we see? (clouds)

Is the total amount of water in the baggie the same after 3 days? (yes, unless the bag was not tightly sealed)

When the water droplets collect at the bottom of the baggie, what stage of the water cycle does this represent? (precipitation)

If the baggie remained tightly sealed, how much water would be in the baggie after one month? (the same amount of water you started with 2 ounces

If the baggie were left on the wall with the seal opened, what would happen to water in the bag? (it would eventually all evaporate into the surrounding atmosphere)

How would your miniature water cycle be affected if the bag was placed in a cool, shady area instead of a hot, sunny area? (the rate of evaporation would be much lower)

How much water was left in the cup after three days? (answers will vary)

2. Have students complete the Explain/Evaluate section on the second page of the CYCLE IN A BAG lab sheet.

3. Remind students that although they can’t always see it happening, the water cycle is

constantly occurring all around them. Emphasize the idea that the Earth contains the same amount of water today that it contained millions of years ago. At different times in the Earth’s history, the water might be distributed differently, but the total amount of water never changes; it is constantly moving through a repeating cycle.

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4. Ask students if they think we really need to worry about running out of useable water since the total amount of water on Earth remains constant.

5. Develop the idea that although water on Earth is abundant overall, the vast majority

of water on Earth is either trapped as frozen ice or found as salt water in the oceans. Explain that 97% of the Earth’s water is saltwater in the ocean and 2% of the Earth’s water is frozen. Of all the water available on Earth, only about one gallon out of every hundred gallons can be used for drinking. As a result, we must be careful to conserve our available fresh drinking water and protect it from contamination and pollution

Mini Water CYCLE IN A BAG Name_____________________________ Date_______________________ DIRECTIONS: Use the materials provided by your teacher to make a mini water cycle in a bag. Remember to mark the starting water level in your cup and write your names on the top bag label. Tape the baggie on the outdoor wall at an angle like a rhombus with the cup of water at the bottom. Record your predictions and daily observations in the spaces below. Essential Question: What will happen to water in a cup if the cup is placed inside a sealed bag and left in a warm area? Prediction: If a cup with water is placed inside a sealed bag and left in a warm area, then the water in the cup will ______________________________________________ _____________________________________________________________________ DAY 1 DAY 2 DAY 3

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Predictions: Observations:

Predictions: Observations:

Predictions: Observations:

Explain/Evaluate: (teacher)

1. What difference did you observe between Day 1, Day 2 and Day 3? (Look at location and color of water.) ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

2. Draw arrows to indicate the path of the water in the water cycle bag below. Label

evaporation, condensation and precipitation in this model of the water cycle.

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3. Draw arrows to indicate the path of water in the picture below. Label evaporation,

condensation and precipitation on this drawing of the Earth’s cycle.

Extension:

Students can further apply what they have learned by doing the My Life As A Drip activity, where they imagine that they are a drop of water, and write a short story about where they think they came from (in the context of the water cycle).

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LAB # 8: AROUND AND AROUND IT GOES! Grade 5 Essential lab (Student’s version)

Name: ______________________________________ Date __________________ The water cycle is a never-ending cycle that includes evaporation, condensation, and precipitation. The sun is the energy that keeps the cycle moving. The heat energy from the sun changes water into vapor. This invisible vapor then condenses and forms billions of droplets that make up clouds. The moisture from the clouds returns to the earth as rain, snow, or other forms of precipitation. Temperature plays an integral role in this never-ending process by affecting the rate of evaporation and the type of precipitation (e.g., rain, snow, ice).

CYCLE IN A BAG

DIRECTIONS: Use the materials provided by your teacher to make a mini water cycle in a bag. Remember to mark the starting water level in your cup and write your names on the top bag label. Tape the bag on the outdoor wall at an angle like a diamond with the cup of water at the bottom. Record your predictions and daily observations in the spaces below.

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Essential Question: What will happen to water in a cup if the cup is placed inside a sealed bag and left in a warm area? Prediction: If a cup with water is placed inside a sealed bag and left in a warm area, then the water in the cup will ______________________________________________ _____________________________________________________________________ DAY 1 DAY 2 DAY 3 Predictions:

Observations:

Predictions:

Observations:

Predictions:

Observations:

Explain/Evaluate:

1. What difference did you observe between Day 1, Day 2 and Day 3? (Look at

location and color of water.)

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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2. Draw arrows to indicate the path of the water in the water cycle bag below. Label

evaporation, condensation and precipitation in this model of the water cycle.

3. Draw arrows to indicate the path of water in the picture below. Label evaporation,

condensation and precipitation on this drawing of the Earth’s cycle.