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Science - 5th Grade
Standard 1 Objective 1
Science - 5th Grade
Standard 1 Objective 2
After completing this activity students will discover that the weight of ice / water will not change after it undergoes melting or freezing.
For each group:
Your students may know that ice will float on water, but they may not know that a volume of water has the same weight whether it is frozen or liquid.
1-Use science process and thinking skills.
2-Manifest scientific attitudes and interests.
3-Understand science concepts and principles.
4-Communicate effectively using science language and reasoning.
Invitation to Learn:
This demonstration will help to grab your students' attention and introduce the activity. To prepare, fill a plastic locking bag with ice cubes (leave it in a freezer until you are ready to do the demonstration). Fill another plastic locking bag mostly full of water and zip it closed.
Begin by showing the class the two bags and asking them to predict what will happen when you stick a sharp pencil into each of the bags. Stick the pencil into the bag of ice. Ask: Why didn't anything leak out? Next hold the bag of water over a large bowl or bucket and quickly stick the pencil through both sides. No water should leak out. (You should practice this before class.) Ask the class to explain why the water didn't leak out. (The plastic shrank together and sealed the hole around the pencil.)
Make a T-chart or Venn Diagram on the board and have the students list the properties of the ice on one side and the water on the other side. Remind students that weight is a property of matter. Ask: If I took a bag of water and froze it, would it weigh more before it was frozen of after it was frozen? Listen to their answers and explain that today they are going to do an experiment to discover the correct answer to that question.
Cooperative teams of 3-5 should complete the following procedures: (see Team Procedures")
After students have completed the activity allow them to share what they have learned. Discuss the statement: The weight of a specified quantity of water (liquid) is equal to the weight of the same quantity of ice (solid). Is this statement always true? Is freezing a physical change or a chemical reaction? Why? (No new substance is created; the water just goes through a physical change.) Is this statement true for all forms of matter? How would you test other types of matter?
You may wish to allow students to investigate other types of matter. (See Possible Extensions.)
After students have discovered that a specified quantity of water has the same weight, whether frozen or solid, challenge the teams to design an experiment to learn if the same is true for other types of matter. Have the students think of common things that melt and freeze at temperatures that can safely be attained in the classroom. (Many items can be safely melted in the classroom by placing them in a Mason Jar then placing the jar in a pan of water and heating the water on a hot plate. Or, try placing the items on aluminum foil under an adjustable desk lamp.) These items might include chocolate, butter, ice cream, wax, cooking oil, or shortening.
Have each team select a different substance to test and write step-by-step procedures for conducting the experiment. Allow teams to share their data after completing the experiment. Work with each team to ensure that safety concerns are addressed while melting and freezing the substances, and that neat and accurate data is collected.
Use this rubric to assess your students ' performances:
Student 's Name ____________________________________
||Descriptions and data clear and accurate. All observations
||Descriptions and data mostly clear and accurate. All observations
||Descriptions and data somewhat clear and accurate. All obervations
|Descriptions and data unclear and inaccurate. All observations incomplete.|
|Used time well and focused attention on the activity.||Used time fairly well. Stayed focused on the activity most
of the time.
||Did the activity but did not appear very interested. Focus
was lost on several occasions.
||Participation was minimal OR student seemed negative about
This lesson is part of the Fifth Grade Science Teacher Resource Book (TRB3) http://www.usoe.org/curr/science/core/5th/TRB5/. The TRB3 is designed to be your textbook in teaching science curriculum to your students. This book covers all the objectives of each standard and benchmark. If taught efficiently, a student should do well on the End-of-Level (CRT) tests. The TRB3 is designed for teachers who know very little about science, as well as for teachers who have a broad understanding of science.