Grade: Senior
Subject: Language

#3861. Life Cycle Of A Star

Science, level: Elementary
Posted Mon Dec 18 19:01:38 PST 2006 by Meghan Webb (
Huntington, WV
Activity Time: 45-60 min

The Life Cycle of a Star:
A Focus on the Sun

Focus Group: Grade 4

Setting: Classroom

Goal of Lesson: To investigate the life cycle of the sun.

Objectives of Lesson:
Upon completion of this lesson the students will be able to:
1.) describe the characteristics of a star,
2.) describe what a force is,
3.) classify the sun as a star,
4.) create the life cycle of the sun through a flipbook activity.

Alignment with WV CSO's:
SC.4.3.1 identify that systems are made of parts that interact with one another.
SC.4.3.3 observe that changes occur gradually, repetitively, or randomly within the environment and question causes of changes.
SC.4.4.30 identify the sun as a star.

Heavy White Paper 3"x5" (15-20 sheets per student for flipbooks)
Finished Flipbook for Demonstration
Crayons, Markers, or Colored Pencils
Stapler or Hole Punch (Yarn)
Texts with pictures of information about the life cycles of stars
Power Point Presentation

Safety Concerns: None

1. Pre-assessment:

What is a star? Is the sun a star?

A good way to begin this discussion is by showing the students a picture slideshow of various types of stars. Talk about the different types of stars that are found in the universe. How are stars born? How long do they live? How do they die?

2. Exploration:
The teacher should begin the exploration section by teaching the students about the life of a star like the sun through a Power Point Presentation. The teacher should also explain to the students how stars are formed, how long they live, and how they die.

Outline of Power Point Presentation:
The Life Cycle of a Star:
A Focus on the Sun

What is a STAR?
A star is a big ball of gas that gives off heat and light. Stars are formed from gravity and dust in outer space. Stars evolve, or change, over time. It may take millions of years or it may take billions of years for a star to complete its life cycle.

There are many types of stars.
Can you think of a star?
Here's a Hint
The sun is star!

The Sun is by far the largest object in the solar system. It contains more than 99.8% of the total mass of the Solar System.
The sun provides life for Planet Earth.
How would life on Earth be different without the sun?
Would there even be life?

How old is the Sun?
Scientists suspect that the sun is almost 4.6 billion years old. Scientists also believe that the sun has enough fuel in it to live on for about 5 billion more years.
The Sun is our own special star yet, as stars go, it is a very average star. There are stars far brighter, fainter, hotter and cooler than the Sun.

Medium mass stars, like our Sun, live by burning the hydrogen that dwells within their cores, turning it into helium. This is what our Sun is doing now. The heat the Sun generates by its nuclear fusion of hydrogen into helium creates an outward pressure. In another 5 billion years, the Sun will have used up all the hydrogen in its core.

The Life Cycle of a Star like the Sun
A Star is Born!

A star is formed from a nebula. A nebula is an interstellar cloud of dust and plasma. A nebula is also known as a stellar nursery.

The Sun is a great ball of gas held together by equal forces. Inside the sun is burning gases like hydrogen and helium. When these gases are burned they push outward. The force of gravity pushes inward. When the forces are equal then an object is stable.

Test Your Force
• Assign each student a partner
• Decide which partner wants to be "A" and which partner wants to be "B"
• Test your force!

How Does a Star Die?
When a star runs out of fuel it dies because the inside force of burning the fuel is not equal to the gravity pushing on it from the outside.

When a main sequence star like the sun begins to die it will turn into. . .. . ...
A Giant!
No, no, not that type of a giant, the sun will turn into a

What is a Red Giant?
A Red Giant is a star like the sun when it begins to die. Because the star has run out of fuel, it begins to cool, and contract. The core of the star is now hotter because of the unequal force of gravity pushing on the star. The star becomes a red giant.

What Next?
We already know that medium mass stars, like our Sun, become red giants. But what happens after that? Well, our red giant Sun is still eating up helium and cranking out carbon. But when it's finished its helium, it isn't quite hot enough to be able to burn the carbon it created. What now?
What will the sun turn into next?

A Dwarf!
No, No, not that type of dwarf. The sun will turn into a

What is a White Dwarf?
A white dwarf is a star about the size of the earth. A white dwarf is an astronomical object which is produced when a low or medium mass star dies. A white dwarf is one of the densest forms of matter. The higher the density or mass of the white dwarf the smaller the size.
Most white dwarfs are extremely hot and remain hot for an extremely long time.
Is this end to our SUN?

Not Quite!
The White Dwarf will turn into a Black Dwarf

A black dwarf is what is left of a white dwarf star after it cools. Black dwarfs are not visible because they have no more fuel.

Is this FINALLY the End Miss Webb?

Well Almost, I LIED!

The life cycles of stars like the sun take place over millions and billions of years so you guys don't need to worry about the sun starting to die anytime soon. The Universe is a place that is vast beyond imagining because there is so much left to be discovered!

1.) Is the sun a star?
2.) What are some of the characteristics of stars?
3.) What types of stars might the sun turn into when it starts to die?

3. Concept Development:

Question: How would our life be different without the sun? Would there even be life?

Test Your Force:
Gentle arm wresting used to show how forces on an object make it stable or unstable.

1. The teacher should assign each student in the room a partner.
2. One partner will be student "A" and one partner will be student "B".
3. The teacher should have the students clasp hands and emit the same amount of force on each other. Note: The student's arms are stable because each student is emitting an equal amount of force.
4. The teacher should have the students clasp hands again and ask student "A" to relax and student "B" to push. Note: The forces are unbalanced and unstable.
5. Repeat.

4. Concept Application:
The teacher should explain to the students that they will be making a "flipbook" movie to show the life cycle of the sun. In this movie the students will accurately depict the life of the sun though each frame.

5. Assessment/Evaluation:
• Is the sun a star?
• What are the characteristics of stars?
• What is force?
• How does force affect stars?
• What type of stars might the sun turn into when it starts to die?
• Did the student accurately depict the life cycle of the sun through his or her flipbook?

6. Extension:
As an extension to this lesson the teacher could choose to teach the students about other types of stars. The teacher may also choose to teach the students about supernovas, neutron stars, and black holes.

7. Integration:
• This lesson can be integrated into art because the students are sketching and coloring the life cycles of the sun.
• The lesson can be integrated into math because the students could graph stars based on the Hertz-Russell Diagram.