Lesson 8 - Water: Changing States of Matter
Overview: Students will discover that water can be found on Earth in all three states of matter - solid, liquid, and gas. While investigating the water cycle, students will learn that changes in temperature causes water to change from one state to another.
Open_Activity: Ask students why water is important.
Have students brainstorm ways we use water. (cleaning, drinking, cooking, swimming,etc.)

Remind students that yesterday we learned that mixing matter is a physical change.
Today we will use water to create a tasty mixture - lemonade!

As the lemonade is being made, students will complete a pre-writing sheet which lists the materials needed and the steps taken to make lemonade.
(THIS WRITING ACTIVITY IS ONE OF THE REQUIRED WRITING ASSIGNMENTS FOR 2ND GRADERS - WRITING A HOW-TO PARAGRAPH.)
Keep the pre-writing sheets for later use in writing the first draft of the how-to paragraph.
Component: Students will work at desks
Time: 45 minutes
Participants: Whole class
Procedure: Students will observe water changing states in Changes in Ice experiment.
  • Display an ice cube on a plate. Have students tell what the ice cube is made of (water) and to identify whether it is a solid, liquid, or gas (solid).
  • Provide each student with Changes in Ice recording sheet (in Handout section).
  • Have students predict what will happen to the ice cube after one hour and after four days.
  • Students will record observations by drawing pictures to show what happened to the ice cube during the experiment.
  • After experiment, ask students: What caused the ice cube to change from one state to another? (changes in temperature)

    Once the ice experiment is set up, tell students that water is unique because it can be found on Earth in all 3 states - solid, liquid, and gas.
    What are examples of water as a liquid?(drinking water, rain, lake, pond, river)
    What are examples of water as a solid? (ice cubes, icicles, snow, sleet, hail)
    What are examples of water as a gas? (water vapor)

    Tell students that water changing from one state to another is part of the water cycle which causes rain.

    Visit the following website: www.kidzone.ws/water/ to learn more about The Water Cycle. This site contains Water Cycle Activity Pages, which include suggested activities that can be done at home to demonstrate the Water Cycle.

    If teachers have the new Harcourt Science textbooks available, Unit E, Ch.2, Lesson 2 - How Can Water Change? (p.E38-E43)can be read and discussed.

    		•
    Expectation: Students will name ways that we use water.
    Students will observe that water changes from one state of matter to another.
    Students will describe how water can be made to change from one state to another.
    Students will explain how water in all three states are a part of the water cycle.
    Questions: Why do you use warm water? boiling water? cold water?
    What causes ice to melt?
    What causes water to boil?
    What causes water to freeze?
    If icicles are melting outside, what can you infer about the temperature?
    What happens when water evaporates?(liquid changes into water vapor)
    What helps cause water in a puddle to evaporate? (heat from the sun)
    Why can't you see water vapor? (it is a gas and you cannot see it)
    What makes water change its form?
    Evaluation: Participation in discussions Completed recording sheet for Changes in Ice experiment
    Close_Act: Return to the ice cube experiment (Changes in Ice) and record how the ice cube has changed after one hour.
    Hints/Tips: Preview the Water Cycle website beforehand. You may want to print out some of the activity sheets for students to work on.
    Web Addresses
      The Water Cycle http://www.kidzone.ws/water/
     
     
     
     
    Handouts, Activity Sheets, Etc.
    changesinice.doc Changes in Ice recording sheet (Word document)