Sink or Float: A Watery Investigation!

Science Grades 2nd Grade 5:51 Video
Print Lesson Plan Watch Video

Lesson Description

Explore why some objects sink and others float in water. Discover the magic of density with a fun, hands-on experiment!

Video Resource

Sink or Float?

SciShow Kids

Duration: 5:51
Watch on YouTube

Key Concepts

  • Sinking
  • Floating
  • Density

Learning Objectives

  • Students will be able to predict whether an object will sink or float.
  • Students will be able to conduct a simple experiment to test their predictions.
  • Students will be able to explain that density affects whether an object sinks or floats.

Educator Instructions

  • Introduction (5 mins)
    Engage students by asking if they've ever wondered why some things sink and others float. Show the SciShow Kids video 'Sink or Float?' to introduce the experiment.
  • Materials and Prediction (10 mins)
    Gather a variety of objects (penny, stick, metal spoon, plastic spoon, rock, leaf, etc.). Have students examine each object and predict whether it will sink or float. Create a chart to record predictions.
  • Experiment (15 mins)
    Fill a clear container with water. One by one, have students place each object in the water and observe what happens. Record the results on the chart.
  • Discussion (10 mins)
    Discuss the results. Were the predictions correct? What did the objects that sank have in common? What about the objects that floated? Introduce the concept of density in simple terms, like the marble example from the video. Relate it to how close or far apart the 'tiny pieces' inside are.
  • Wrap Up (5 mins)
    Review the key concepts. Ask students what they learned about sinking, floating, and density. Encourage them to explore sinking and floating with other objects at home (with adult supervision).

Interactive Exercises

  • Sink or Float Guessing Game
    Show pictures of different objects and have students vote whether they think each object will sink or float.

Discussion Questions

  • What makes some things sink and other things float?
  • What is density, and how does it affect if something sinks or floats?
  • Can you think of other objects that would sink or float?

Skills Developed

  • Observation
  • Prediction
  • Data collection
  • Critical thinking
  • Scientific Investigation

Multiple Choice Questions

Question 1:

What happens when something sinks?

Correct Answer: It goes to the bottom

Question 2:

What happens when something floats?

Correct Answer: It stays on top

Question 3:

Which of these will probably sink?

Correct Answer: A rock

Question 4:

Which of these will probably float?

Correct Answer: A boat

Question 5:

What is density?

Correct Answer: How much stuff is packed into something

Question 6:

If something is MORE dense than water, it will...

Correct Answer: Sink

Question 7:

If something is LESS dense than water, it will...

Correct Answer: Float

Question 8:

A metal spoon is usually ______ dense than a plastic spoon.

Correct Answer: More

Question 9:

What did the ducks in the video help with?

Correct Answer: Predicting if things would sink or float

Question 10:

What is something important to do before you put things in water for an experiment?

Correct Answer: Ask a grown-up

Fill in the Blank Questions

Question 1:

When something goes to the bottom of the water, it ______.

Correct Answer: sinks

Question 2:

When something stays on top of the water, it ______.

Correct Answer: floats

Question 3:

A penny is more ______ than a leaf.

Correct Answer: dense

Question 4:

Density tells us how much stuff is ______ into something.

Correct Answer: packed

Question 5:

If an object is less dense than water, it will ______.

Correct Answer: float

Question 6:

If an object is more dense than water, it will ______.

Correct Answer: sink

Question 7:

The tiny things that make up everything are called ______.

Correct Answer: particles

Question 8:

In the video, Jessi used ______ to explain particles.

Correct Answer: marbles

Question 9:

The metal spoon ______ in the water.

Correct Answer: sank

Question 10:

The stick ______ in the water.

Correct Answer: floated

Educational Standards

2.PS1.1:[Standard] Plan and conduct an investigation to describe and classify different kinds of materials by their observable properties. 2.PS1.2:[Standard] Analyze data obtained from testing different materials to determine which materials have the properties that are best suited for the intended purpose.*

Teaching Materials

Download ready-to-use materials for this lesson:

Student Worksheet Classroom Slides Assessment Quiz
Add to Google Classroom

User Actions

Sign in to save this lesson plan to your favorites.

Sign In

Share This Lesson

Related Lesson Plans