GRADES K-2 UNIT OUTLINE

Summary of Purpose for the Unit

This unit was designed to provide primary students with opportunities to investigate and observe water as a solid, a liquid, and a gas. It uses text and hands-on experiences to answer the questions How does water change from a solid to a liquid to a gas? and Where can we see these changes in nature?

Standards Alignment

National Science Education Standards: Science Content Standards

Science content standards are found in Chapter 6 of the National Science Education Standards.

Science as Inquiry (Grades K-4)

• Ask questions about objects, organisms, and events in the environment
• Employ simple equipment and tools to gather data and extend the senses
• Use data to construct a reasonable explanation
• Communicate investigations and explanations

Physical Science (Grades K-4)

• Properties of Objects and Materials

IRA/NCTE Standards for the English Language Arts

View the standards at http://www.ncte.org/standards.

1 – Students read a wide range of print and nonprint texts.

3 – Students apply a wide range of strategies to comprehend, interpret, evaluate, and appreciate texts.

4 – Students adjust their use of spoken, written, and visual language (e.g., conventions, style, vocabulary) to communicate effectively with a variety of audiences and for different purposes.

5 – Students employ a wide range of strategies as they write and use different writing process elements appropriately to communicate with different audiences for a variety of purposes.

11 – Students participate as knowledgeable, reflective, creative, and critical members of a variety of literacy communities.

12 – Students use spoken, written, and visual language to accomplish their own purposes.

Unit Outline

Engage

Read Lulie the Iceberg by Takamado no Miya Hisako (from this issue’s virtual bookshelf) to students. You may wish to simulate an iceberg by freezing a large chunk of ice and placing it in a fishbowl, an aquarium, or other clear container filled with water. Allow students to observe the iceberg. Ask them to discuss what they know about ice and liquid water. What do they know about melting ice (like Lulie the iceberg in the text)? Record student ideas on chart paper or on a KWL chart posted in a prominent location.

Explore

During this phase, provide opportunities for students to investigate water-changing states. These opportunities may be conducted as whole-class activities or as learning centers. Possibilities include:

• Place two pans of water on a windowsill – one covered, the other uncovered. Mark the water levels and then leave the two pans for several hours or overnight. Mark the water levels again. How did the water change? Did the same changes happen in the open and closed containers? Why or why not?
• Students can “paint” with water. What happens to their paintings over time? Where does the water go?
• Students can experiment with melting ice cubes as described in the “The Great Meltdown” section of the lesson The Wonderful World of Water.
• Have students breathe on a hand mirror and observe the fog (condensed water vapor) that forms. Or have them hold a hand in front of their mouth and breathe slowly into their palm and feel the wetness. Where does that water come from?
• Have students observe a pan of boiling water. For safety reasons, this should be conducted as a teacher demonstration. Students should be instructed not to lean over the pan or come near the burner, and should wear safety goggles. What do students observe? What is happening to the water?

Other ideas can be found in the lessons The Wonderful World of Water, The Mystery of the Sponge, and Water Magicians.

At this point, students should not be expected to have a clear understanding of how water changes states from solid to liquid to gas, or a command of the scientific vocabulary. These will be developed in the Explain phase of the unit. Students should discuss their findings and add to or revise the chart or KWL chart as needed.

Explain

Read and discuss the Water series by Helen Frost (from this issue’s virtual bookshelf) with students. The series includes four books: Water As a Gas, Water As a Liquid, Water As a Solid, and The Water Cycle. Discussion should center around water in its three states, as well as the ways in which water changes states. You may wish to repeat demonstrations or activities from the Explore phase in conjunction with the scientific explanations found in the text. Read-alouds, repeated demonstrations, and discussions should be used to help students develop an age-appropriate understanding of water as a solid, a liquid, and a gas. Students should also develop control over the appropriate scientific vocabulary during this time.

Please note that the concept of water as a gas and the process of evaporation are difficult for students to understand. While teachers should not expect detailed mastery of these concepts, they can expose students to them on an introductory level. Investigations involving heating and evaporation can also be used to develop important inquiry skills such as predicting and observing. For more information, please see Common Misconceptions About States and Changes of Matter and the Water Cycle.

At this point, students are ready to demonstrate what they’ve learned about water as a solid, a liquid, and a gas. They should be able to give examples of water in its three states, explain how water changes states, and use scientific vocabulary (solid, liquid, gas, melting, freezing). You might choose one of the following options:

• A journal. Ask students and their families to keep a journal that answers the question Where did I see water this week? Students might note the water in the bathtub, the steam in the shower, ice cubes in their drink at a restaurant, rain, snow, and so on. Each journal entry might include a picture (drawn by the student or a digital photograph) and an explanation of what was seen. At the end of the week, students could bring in their journals and share examples with the class. Assessment of student work would include both the product (the journal) and students’ ability to discuss their work in class.

• A collage. The class (or individual families) might “collect” examples of water around the school building, at home, and in nature and record them on a poster or collage. Pictures or words might be used for each category, and categories could include both the three states of water as well as water changing states by freezing, melting, or evaporating. Assessment might involve asking individual students to select examples from each category and write about them or discuss them with the teacher in an individual conference.

• Picture sort. Print pictures of water and ask students to sort them into three categories: solids, liquids, and gases. Students could then explain how the water changes from one state to another, using the pictures as a guide. Note: This activity works best with the solid and liquid phases of matter. It is difficult to represent water vapor in a picture – pictures of fog, mist, and clouds are actually of condensed (liquid) water. They prove that there is water vapor in the air, but they don’t show it directly.

Expand

This unit leads naturally into an overview of the water cycle, and of the Sun’s role in the water cycle. The lessons The Wonderful World of Water and Rain, Ice, Steam: Using Reading to Support Inquiry About the Water Cycle provide instructional sequences for introducing the water cycle to primary students. The Warmth of the Sun uses indoor and outdoor activities to help students understand the Sun’s role in heating and warming Earth’s air, land, and water.

Assess

This unit provides opportunities for both formative and summative assessment.

Formative Assessment

Formative assessment is conducted throughout the unit. For example:

• Student ideas recorded on chart paper or the KWL chart at the start of the unit provide insight into the prior knowledge (and misconceptions) that students bring to the topic. Additionally, revisions and additions to the chart during the unit provide evidence of student learning.
• Student participation in the learning centers and discussions during the Explore and Explain phases provide insight into what students have learned and what they still do not understand. Reteach and modify lessons as needed.

Summative Assessment

Student work in the Explain phase – whether a journal, a collage, or verbal explanations – provides evidence of understanding of the states of matter and how matter changes state. This is best assessed with a rubric that includes criteria for scientific accuracy, use of vocabulary, quality of written/verbal explanations, and illustrations (if included in the assignment).

GRADES 3-5 UNIT OUTLINE

Summary of Purpose for the Unit

This unit was designed to provide elementary students with opportunities to observe and model the states of matter and the water cycle. It uses hands-on experiences and text to answer the questions Where do we find water on Earth? and How does water change from one state to another?

Standards Alignment

National Science Education Standards: Science Content Standards

Science content standards are found in Chapter 6 of the National Science Education Standards.

Science as Inquiry (Grades K-4 and 5-8)

• Ask questions about objects, organisms, and events in the environment
• Employ simple equipment and tools to gather data and extend the senses
• Use data to construct a reasonable explanation
• Communicate investigations and explanations

Earth and Space Science

• Changes in the Earth and Sky (Grades K-4)
• Structure of the Earth system (Grades 5-8)

IRA/NCTE Standards for the English Language Arts

View the standards at http://www.ncte.org/standards.

1 – Students read a wide range of print and nonprint texts.

3 – Students apply a wide range of strategies to comprehend, interpret, evaluate, and appreciate texts.

4 – Students adjust their use of spoken, written, and visual language (e.g., conventions, style, vocabulary) to communicate effectively with a variety of audiences and for different purposes.

5 – Students employ a wide range of strategies as they write and use different writing process elements appropriately to communicate with different audiences for a variety of purposes.

11 – Students participate as knowledgeable, reflective, creative, and critical members of a variety of literacy communities.

12 – Students use spoken, written, and visual language to accomplish their own purposes.

Unit Outline

Engage

Begin by asking students to consider the questions posed in our formative assessment probe titled How Much Water?, How does the amount of water on Earth now compare with the amount 1,000 years ago? You might choose to administer the probe to students individually, or pose the question for pairs, small groups, or the class to discuss. For more information about misconceptions and formative assessment, see Common Misconceptions About States and Changes of Matter and the Water Cycle.

Explore

In this phase, students should begin to explore the questions  Where do we find water on Earth? and How does water change from one state to another? Students should not be expected to be proficient with scientific explanations or vocabulary at this time.

In the investigation Where is Water Found?, students brainstorm where water is found on Earth and use pennies to represent the distribution of fresh water, salt water, and ice (glaciers). The instructional procedure also directs teachers to discuss the small, yet important, percentage of water that exists as water vapor in the air. Once students have an understanding of the three states of water, move to explorations of how water changes state. The following lessons provide opportunities for inquiry around the role of heat energy in melting, evaporation, and condensation:

Why Does a Puddle Shrink?
Students investigate the role heat energy plays in evaporation.

Condensation Chambers
Students create condensation chambers and observe the process of water condensation on cool surfaces.

Heat Energy and Water
This activity is designed to develop the concept of heat’s influence on solid and liquid water. The activity should also help students differentiate between heat and temperature.

Blue Ice Cube Melt
In this experiment, students observe that blue ice cubes (which represent glaciers) can melt under pressure.

Can You Melt a Glacier with Pressure?
Similar to Blue Ice Cube Melt. Students observe a model glacier and learn that it can melt (and move) from the pressure of its immense weight.
Teachers may wish to omit the assessment portions of the lessons (or use them as formative assessment) since the lessons are part of the Explore phase of the unit. Students should be expected to record questions, data, and explanations in science notebooks, graphic organizers, or chart paper posted in the classroom. They should not be expected to have mastery of the scientific explanations and vocabulary, however.

Explain

Read aloud (or have students or small groups read) informational text about the water cycle. Possible selections include Water, Water Everywhere: A Book about the Water Cycle by Melvin and Gilda Berger, Water by Christin Ditchfield, The Water Cycle by Therese Greenaway (all from our Water, Ice, and Snow virtual bookshelf) and  Did a Dinosaur Drink This Water? by Robert E. Wells. Conversation around the texts should build on students’ experiences and observations during the Explore phase and develop their understanding of vocabulary terms such as evaporation, condensation, precipitation, and water vapor.

Next, use the lesson Water on the Move, in which students play a game to deepen their understanding of the water cycle. Students assume the role of water and travel back and forth between locations on a worksheet depicting the water cycle and explain how they change from one state to another as they go. This activity can be modified to include locations and geographic features similar to those found in your hometown. It could also be modified to be a kinesthetic activity in which students move from station to station around the classroom, the gymnasium, or the schoolyard. Student explanations of the changes of state of the water throughout the cycle are the most important part of the activity, regardless of how it is conducted. Teachers should circulate through the room or schoolyard and listen to student explanations as a means of formative assessment, then clarify or reteach as needed.

Following this activity, teachers should proceed to the summative assessment task (see below) before continuing to the Expand phase of the unit.

Expand

Ideally, student questions drive the Expand phase of any learning cycle unit. However, teachers may wish to anticipate possible topics that may arise as a result of a study of the water cycle. Possibilities include:

• A study of pollution and water-quality issues such as runoff. Students could investigate the health of local bodies of water.
• A study of erosion. Our issue Earth’s Changing Surface provides a wealth of resources on this topic.
• Water conservation. The Down the Drain project asks students to analyze water-usage data from their own lives and around the world. Read more at Connecting Classrooms, Sharing Real Data.
• The Sun’s role in heating and warming Earth’s air, land, and water. Our issue Energy and the Polar Environment provides resources related to solar energy and the absorption and reflection of light.

Assess

Formative Assessment

Formative assessment is conducted throughout the unit. For example:

• Student responses to the assessment probe How Much Water? provide an initial look at student understanding.
• Student engagement and participation in the activities during the Explore phase provide insight into their developing knowledge, as well as their ability to use science process skills and conduct inquiry.
• Discussion around the informational texts in the Explain phase allows for questioning, clarification, and reteaching as needed.
• Observation of student participation and explanations in the Water on the Move game provides insight into student understanding of the water cycle.

Summative Assessment

Summative assessment should focus on students’ abilities to explain the water cycle. This can be accomplished in many different ways. A few possibilities include:

• Students might refer back to their experiences in the Water on the Move lesson and write a narrative story about the journey of a drop of water. The lesson Water World Story provides guidance for writing a six-frame story, although the instructional procedure can be modified to fit your needs.
• Students might return to the assessment probe How Much Water?, review their prior responses, and write new responses based on their current understanding of the water cycle. This is a great way to encourage reflective thought and allow students to see the progression in their scientific understanding.
• Students might use digital photos of water in various states and locations around the world and create a VoiceThread explaining the water cycle.

Regardless of the nature of the assessment task, student work can be scored using a rubric that includes criteria for both scientific concepts and correct use of vocabulary.