The Engineering Place (K-20 Outreach)

Sink or float? (k-2nd)

Lesson plan developed by Elizabeth Goodson

Objective: The students will explore whether different objects sink or float in water using the scientific method.

Overview: This lesson will emphasize the scientific method, properties and relationships of objects and classifying objects.

Materials:

1. Clear plastic container
2. Paper to make predictions and observations
3. Water
4. Items that sink
5. Items that float
6. Christopher Columbus by Stephen Krensky

Getting Ready:

• Fill plastic container about half full with water
• Have children sit where they can listen to the story and see the demonstration.

Activity:

• Read Christopher Columbus
• Discuss the book
  • Columbus leaves Spain
  • Sails to “Indies”
    
  • On his way back to Spain he thinks he will sink
• Ask children: Do you remember when Columbus thought his boat would sink?
• Explain scientific method:
  1. Scientific Method is a way to look at something as a scientist would look at it by performing an experiment.
     
  2. Observe and ask questions
     
  3. Make a hypothesis — GUESS
     
  4. Plan your test
  5. Conduct your test and gather data
     
  6. Draw conclusions and share results
     
  7. Investigate further
• Explain Activity: We are going to take different objects and see if they float or sink.
• Ask children: What kinds of questions might we ask for this experiment?
  • What items do we know that will sink?
    
  • Float?
    
  • Does it depend on the size or what the object is made of?

Procedure:

1. Make hypothesis – guess about what will happen
   
2. Plan our test
   
3. Conduct our test — pick an item from the bag and place the object in the water and record what happens
   
4. Draw conclusions and share results — group the items that floated or sank
   
5. Discuss the differences in predictions and what the children observed.
   
6. Investigate further — What other items might we want to test?

Closure:

• Scientists use this method every day to figure out different problems.
• What was the method called?
• Does something that feels heavy always sink?
• What kind of material would we want our boat to be made of if we were to sail on a trip like Christopher Columbus?

Resources:

Christopher Columbus by Stephen Krensky

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