Sink or Float?

tplaza

Tier 1

Lesson Plan

Sink or Float Lesson Plan

Students will understand the principles of buoyancy and density by predicting and testing whether different objects sink or float, reinforcing scientific inquiry skills.

This lesson promotes critical scientific thinking while demonstrating real-world applications of density and buoyancy, essential for understanding physical science concepts.

Audience

7th Grade Science Students

Time

30 minutes

Approach

Interactive experiment with prediction, testing, and discussion.

Materials

Sink or Float Lesson Plan, Water Container, Variety of Objects (e.g., cork, rock, plastic toy), Prediction Recording Sheet, and Pencil

Prep

Preparation

5 minutes

Review the Sink or Float Lesson Plan for key concepts.
Gather all materials including water containers and various objects.
Prepare prediction recording sheets for each student or group.
Set up the classroom for easy access to materials during the experiment.

Step 1

Introduction

5 minutes

Briefly explain the concepts of density and buoyancy.
Ask students to share examples of objects that might sink or float.
Discuss how these properties affect whether objects sink or float.

Step 2

Prediction Activity

5 minutes

Distribute prediction recording sheets.
Have students predict whether each object will sink or float.
Encourage students to explain their reasoning.

Step 3

Experiment

10 minutes

Divide students into small groups.
Allow each group to test the objects in the water container.
Instruct groups to record actual outcomes and compare against their predictions.

Step 4

Discussion and Conclusion

5 minutes

Bring the class together to discuss the results.
Ask guiding questions: What surprised you? How did the actual outcomes compare with your predictions?
Reinforce the concepts of density and buoyancy with examples from the activity.

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Slide Deck

Sink or Float?

Welcome! Today we'll explore why some objects sink while others float.

Introduce the lesson, explain that today’s inquiry will focus on buoyancy and density. Encourage student engagement from the very start.

Key Concepts: Buoyancy & Density

Buoyancy: The upward force that water exerts on an object.

Density: The amount of mass per unit of volume. (Objects with lower density than water float.)

Explain the concepts of density and buoyancy using simple examples. Add pictures or diagrams if possible.

Prediction Activity

Predict: Will these objects sink or float?

Why do you think so?

Record your predictions on the provided sheets.

Invite students to think about objects they know and make predictions based on their understanding of density.

Hands-on Experiment

Test objects in water and record the results.

Work in small groups and compare predictions with actual outcomes.

Describe the experimental process. Explain in detail the preparation and testing of objects. Encourage group work and careful observation.

Discussion & Conclusion

What surprised you?

How did your predictions compare with the test results?

Let's discuss how density and buoyancy impact objects in water.

Facilitate a class discussion, asking guiding questions and reinforcing the key learning points about buoyancy and density. Discuss any surprises or insights.

Worksheet

Prediction Recording Sheet

This worksheet is designed to help you record your predictions and the actual outcomes during our Sink or Float experiment. Fill in each section as you work through the activity. Use the space provided to write your observations and any questions that come to mind.

Instructions:

Write down the name of the object you are testing.
Predict whether the object will sink or float and explain why.
Record the actual outcome when you test the object.
Note any observations or questions you have about the outcome.

Worksheet Table

Object Name	Prediction (Sink or Float and why?)	Actual Result (Sink or Float)	Observations/Notes

Feel free to add extra rows if you test more objects!

Once you have completed the table, we'll discuss your findings as a class.