Lesson 3rd Grade 04/15

HISD 3rd Grade Science
Forces and Motion

M3 L13
April 15, 2024

14

Forces and Motion

LO: SWBAT observe and describe the effect of
gravity on an object.

DOL: Given a problem, SW explain the effect of
gravity on an object in at least 2 of 3 questions.

TEKS SCI 3.6B Demonstrate and observe how position and motion can be changed by pushing and pulling objects such as swings, balls, and wagons.
TEKS SCI 3.6C Observe forces such as magnetism and gravity acting on objects.

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Essential Understandings &

Guiding Questions

What can cause the motion of an object to change?

What happens when multiple forces act on an object at the same time?

Open Ended

What can cause the motion of an object to change?

Open Ended

What happens when multiple forces act on an object at the same time?

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Lesson Vocabulary

gravity

force

motion

Gravity

the force that pulls objects
toward Earth and causes
objects with mass to
attract to one another

Force

a push or pull that acts on
an object which may cause
a change in an object’s
motion

Motion

the act or process of
moving

Why did the cup fall?

Open Ended

Why did the cup fall?

Sample student response- Explore L13
Activity Guide

How did you cause objects to fall at the Motion Stations?

Open Ended

How did you cause objects to fall at the Motion Stations?

Sample class model- Explore

How could you make an object such as a penny fall to the ground?

What do you think caused the penny to fall rather than continue to go up?

Open Ended

How could you make an object such as a penny fall to the ground?

Open Ended

What do you think caused the penny to fall rather than continue to go up?

A long time ago, a scientist names Isaac Newton was sitting in an
orchard when he observed an apple fall from a tree. The apple made
him curious about what causes objects to fall to the ground.
After many tests and a growing body of evidence, he developed his
law of gravity to describe how objects are pulled to Earth.

Does gravity act on the penny
as it travels upward? Explain

your reasoning.

Do you think gravity acts on

a penny when it is on the

floor?

What force do you think caused the penny

to stop falling and come to rest?

Open Ended

Does gravity act on the penny as it travels upward? Explain your reasoning.

Open Ended

Do you think gravity acts on a penny when it is on the floor?

Open Ended

What force do you think caused the penny to stop falling and come to rest?

Why doesn’t the cup fall when
it is attached to the block with
a string?

What forces are acting on the
cup?

What keeps the cup from
moving?

​Draw your force model in your packet

Open Ended

Why doesn’t the cup fall when
it is attached to the block with
a string?

Open Ended

What forces are acting on the
cup?

Open Ended

What keeps the cup from
moving?

What would happen if we cut the string?

What other forces are exerted on a cup that is resting on the floor?

Open Ended

What would happen if we cut the string?

Open Ended

What other forces are exerted on a cup that is resting on the floor?

1. Draw a force model that

shows the forces acting on
the object while it is at rest.

1. Draw a force model that

shows the forces acting on
the object while it is in
motion.

Draw

1.Draw a force model that shows the forces acting on the object while it is at rest.

Draw

1.Draw a force model that shows the forces acting on the object while it is in motion.

Sample class force model

Claim
When the force exerted on one side of an object is
stronger than the force exerted on the other side, the
object’s motion changes. When the forces exerted on
both sides of an object are equal in strength, the object’s
motion does not change.

How could you use what you’ve learned in
this lesson to make the claim more
precise?

Open Ended

How could you use what you’ve learned in
this lesson to make the claim more
precise?

Claim

★ When the force exerted on one side of an object (i.e.,

left, right, up, or down) is stronger than the force
exerted on the other side, the object’s motion
changes. When the forces exerted on the opposite
sides of an object are equal in strength, the object’s
motion does not change.

Choose an object from the classroom
and draw a model to explain the forces acting on the object.

Draw

Choose an object from the classroom
and draw a model to explain the forces acting on the object.

32

DOL: Given a
problem, SW
explain the effect
of gravity on an
object in at least 2
of 3 questions.

Demonstration of Learning

Multiple Choice

Choose the word that best completes the sentence.

___________ is the force that pulls objects toward Earth.

• Magnetism

• Motion

• Gravity

• Ground

Multiple Choice

When the forces exerted on opposite sides of an object are equal in strength, the object’s motion does not change.

• True

• False

Multiple Choice

Which statement is NOT an example of how gravity affects the motion of objects on Earth?

• Gravity keeps everything in our classroom from floating.

• I dropped a book and it floated up into the air.

• Raindrops fall from clouds to the ground.

• When I jump up in the air, I always come back down.