Lesson 2: The life cycle of a star


This activity will require approximately four 30-minute classes

  • 2 class periods for research
  • 1 class period to prepare poster presentations
  • 1 class period for mini-presentations


Describe how evidence must be continually questioned in order to validate scientific knowledge (e.g., provide examples of ideas, such as the flat Earth, the Earth as the centre of the solar system, and life on Mars, which were or are being challenged to develop new understandings of the natural world) Relationships between science and technology
Describe examples of improvements to the tools and techniques of scientific investigation that have led to new discoveries (e.g., describe examples, such as the lunar buggy, the Canadarm, the Hubble telescope, and space probes, which have extended scientific knowledge)
Draw a conclusion, based on evidence gathered through research and observation, that answers an initial question (e.g., conclude that simulated flour craters are deeper and wider when the marble is heavier or is dropped from greater heights)
Describe the physical characteristics of components of the solar system - specifically, the sun, planets, moons, comets, asteroids, and meteors

General Objectives

Students will investigate the life cycle of a star, recognizing that all stars (including the Sun) have a life cycle that is determined by the mass of the star.

  • Information and Communication Technologies
    • Internet research
  • Visual arts
    • Creating a poster

Lesson Overview

In this lesson, students are assigned a particular phase in the life of a star and will work in groups to research the phase. Students will prepare and present a poster to explain the phase. After all posters have been presented, the student posters will be mounted on the wall according to the correct sequencing.

Materials and Resources

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Research materials

  • library books
  • websites


  • protostar
  • nebula
  • protoplanetary disk
  • star cluster
  • supernova
  • planetary nebula
  • white dwarf
  • black dwarf
  • black hole
  • neutron star

Developing the Lesson

Begin with focus questions:

  • Have you ever wondered how the Sun was born or how long it will live?
  • If stars live for billions of years, how can we ever begin to study their life?
  • How do you think astronomers are able to study the different phases of a star's life?

Commence the activities and remember to have fun.

Explain that the activities will be used to help students become better acquainted with the life cycle of stars and as a results, they will gain a deeper understanding of the Sun.

Divide students into groups of 3; assign each group to research one of the following phases:

  1. protostar (example: the Eagle Nebula, a stellar nursery)
  2. protoplanetary disk and stellar system in formation (example: Orion Nebula)
  3. cluster of young stars (example: the Pleiades)
  4. middle-aged, normal star (example: the Sun)
  5. cluster of older stars—red giant (example: Betelgeuse)
  6. dying stage—supernova, planetary nebula
  7. white dwarf (example: Supernova 1987A)
  8. state of a star—black dwarf, black hole, neutron star (example: Cygnus X-1)

Periodically monitor students' research to ensure that they are on task.

Once students appear to have enough research, direct them to begin assembling their poster presentations. If students are having difficulties with the research, the teacher may wish to use the KWL technique.

When all groups have their posters completed, reassemble the class and begin the presentations beginning with the group who researched the protostar phase. After the groups present, the teacher should interject with connections linking the phases. Proceed with the presentations until all groups have shared their findings.

All posters should be mounted sequentially on the wall.


As a closure to the activities, the teacher recaps the life cycle of a star showing the students the Life Cycle of a Star applet.


The best way to evaluate this activity is to evaluate student participation during group research, as well as the quality/quantity of research. The following rubric may be helpful for evaluations.

Cooperative Learning Rubric
CATEGORY Excellent Good Satisfactory Needs Improvement
Contribution to Group Regularly provides useful ideas to group; contributes a strong effort Often provides useful ideas to group; tries hard Sometimes provides useful ideas to group; does what is required Rarely provides useful ideas to group; may refuse to participate
Quality of Work Highest quality work High quality work Work sometimes needs monitoring or re-doing Work usually needs monitoring or re-doing
Effectiveness Regularly paces work well; does not need to be encouraged to get work done on time Usually paces work well; may have needed some encouragement to get work done on time, but does not hold up group's progress Tends to procrastinate, but always gets work done on time Rarely paces work well; group's progress is held up by inadequate time management
Attitude Never openly critical of project or others' work; positive attitud Rarely openly critical of project or others' work; mostly positive attitude Sometimes openly critical of project or others' work; partially negative attitude Often openly critical of project or others' work; mostly negative attitude
Preparedness Always ready to begin tasks Almost always ready to begin tasks Almost always brings needed materials, but distractions sometimes slow progress Often forgets to bring materials or is rarely ready to begin tasks
Collaboration Almost always contributes to group dynamic by listening, sharing, and supporting others' efforts; encourages  group unity Usually contributes to group dynamic by listening, sharing, and supporting others' efforts; does not create problems for group Sometimes contributes to group dynamic by listening, sharing, and supporting others' efforts; sometimes a poor team player Rarely contributes to group dynamic by listening, sharing, and supporting others' efforts; often a poor team player