Objectives (5 - 7 minutes)

1. Understand the concept of stellar evolution: Students should be able to describe the process of formation and evolution of a star, from its formation from a cloud of interstellar gas and dust, to the end of its life, whether it be a white dwarf, a neutron star, or a supernova.

2. Identify the main stages of stellar evolution: Students should be able to identify and describe the characteristics of the main stages of stellar evolution, including the main sequence stage, red giant, supergiant, and the final stage.

3. Relate stellar evolution to the physics of stars: Students should be able to relate the knowledge acquired about stellar evolution to the principles of physics, such as nuclear fusion, pressure, and gravity.

Secondary objectives:

• Stimulate critical thinking and scientific curiosity: The teacher should encourage students to question and explore the presented concepts, promoting discussion and reflection on the topic.

• Foster independent research: Students should be encouraged to seek additional information on the subject, deepening their understanding and developing autonomous research skills.

Introduction (10 - 12 minutes)

1. Review of previous contents: The teacher should start the class by reminding students of the basic concepts of astronomy and physics that are necessary for understanding the current topic. This may include a review of the universe, galaxies, stars, and the principles of physics such as nuclear fusion and gravity.

2. Problem situation: The teacher should propose two situations to students to stimulate critical thinking and arouse curiosity.

   • The first situation could be: 'Imagine you are an astronaut on a mission to study a star. How would you determine the age and stage of evolution of that star without returning to Earth?'
   • The second situation could be: 'If all stars are born from a cloud of gas and dust, why do not all stars have the same size, brightness, and color?'

3. Contextualization: The teacher should explain to students the importance of studying stellar evolution. It can be mentioned how knowledge about the evolution of stars helps us understand the origin and evolution of the universe, as well as how stars influence the formation and evolution of planetary systems, including our own solar system.

4. Capturing students' attention: The teacher can present two interesting facts to capture students' attention:

   • Fact 1: 'Did you know that, according to scientists, all the gold on Earth was created in a supernova, a stellar explosion?'
   • Fact 2: 'Did you know that stars, like living beings, are born, grow, age, and die? And that the final fate of a star can vary from a small and dense white dwarf to a black hole?'

Development (20 - 25 minutes)

1. Practical activity with a star model (10 - 12 minutes):

   • Materials needed: Balls of different sizes (representing stars of different masses), markers of different colors, small flashlights (representing the energy generated by nuclear fusion), wool threads (representing stellar radiation), and pieces of cardboard (representing space-time curved by stellar gravity).

   • Step by step: Students will be divided into groups of 3 to 4. Each group will receive the necessary materials. The teacher will explain that the objective of the activity is to create a model of a star and describe how it changes throughout its life.

     1. Students will start by drawing a sequence of circles (using balls of different sizes) on the cardboard, each representing a different stage of stellar evolution.
     2. Next, they will mark the stages with markers, identifying them as the main sequence, red giant, supergiant, etc.
     3. Then, they will glue wool threads around the circles to symbolize stellar radiation.
     4. Finally, they will position the flashlights next to the circles to represent the energy generated by nuclear fusion.

   • Conclusion of the activity: After the models are completed, each group will present theirs to the class, explaining the stages of stellar evolution they represent and the changes that occur in each stage. The teacher will mediate, correcting and adding information as necessary.

2. Debate activity on the importance of stellar evolution (5 - 7 minutes):

   • Step by step: The teacher will divide the class into two groups. Each group will receive a list of statements related to the importance of studying stellar evolution.
     1. Students will have a few minutes to discuss the statements in their groups, identifying the pros and cons of each one.
     2. Then, a representative from each group will present their group's conclusions to the class.
     3. The teacher will conclude the activity by emphasizing the importance of studying stellar evolution for understanding the physics of the universe and the origin and evolution of life.

3. Computational simulation activity (5 - 6 minutes):

   • Step by step: The teacher will present students with an interactive computational simulation of the life cycle of a star. This simulation may include the formation of a star from a cloud of gas and dust, the main sequence, the red giant, the supergiant, and the final stage (white dwarf, neutron star, or supernova).

   • Conclusion of the activity: Students will have the opportunity to explore the simulation at their own pace, observing the changes that occur in a star throughout its life. The teacher should circulate around the room, assisting students with questions and encouraging discussion about the simulation.

Return (8 - 10 minutes)

1. Group discussion and reflection (3 - 4 minutes): The teacher should gather all students and promote a general discussion about the conclusions of the groups. This may involve questions like: 'What were the main learnings of each group?' or 'How did the activities help clarify the concept of stellar evolution?'. The goal is to allow students to share what they learned with each other, reinforcing concepts and clarifying possible doubts.

2. Connection with theory (2 - 3 minutes): The teacher should then connect the practical activities carried out with the theory covered in the class. This can be done through questions like: 'How do the changes you observed in your star models relate to the stages of stellar evolution we studied?' or 'How does the simulation you explored resemble what we discussed about stellar evolution?'.

3. Individual reflection (2 - 3 minutes): Finally, the teacher should propose that students reflect individually on what they learned in class. This reflection can be guided by questions like:

   1. 'What was the most important concept you learned today?'
   2. 'What questions have not been answered yet?'.

   The teacher should encourage students to write down their reflections, as this can be useful for future studies and for further deepening their understanding of the subject.

4. Feedback and closure (1 minute): The teacher should thank the students for their participation, provide feedback on the class, and encourage the continuation of studies on stellar evolution. Additionally, students should be reminded of the importance of the topic for understanding the universe and life on Earth, and how the physics of stars plays a fundamental role in many phenomena we observe daily, such as the climate, daylight and night, and the existence of life on Earth.

Conclusion (5 - 7 minutes)

1. Recap of the main contents (2 - 3 minutes): The teacher should recap the main points covered during the class, reinforcing the concept of stellar evolution and the main stages of this process, such as the main sequence, red giant, supergiant, and the final stage. Additionally, it should be highlighted how stellar evolution is closely related to the principles of physics, such as nuclear fusion, pressure, and gravity.

2. Connection between theory, practice, and applications (1 - 2 minutes): The teacher should emphasize how the practical activities and debates carried out in class helped consolidate the theoretical understanding of stellar evolution. Some practical applications of this knowledge should also be mentioned, such as the possibility of determining the age and stage of evolution of a star from astronomical observations, or how the study of stars contributes to our understanding of the universe and the origin and evolution of life.

3. Additional materials (1 minute): The teacher should suggest some additional study materials for students who wish to deepen their knowledge on the subject. This may include books, documentaries, astronomy and physics websites, and astronomical simulation apps. The teacher may also provide links to online articles and videos that explain in more detail the concepts discussed during the class.

4. Importance of the subject (1 minute): Finally, the teacher should emphasize the importance of studying stellar evolution. It should be highlighted how understanding this process helps us better understand the universe we live in, from the origin and evolution of stars to the formation of chemical elements and the possibility of life on other planets. Additionally, it should be emphasized how the physics of stars plays a fundamental role in many aspects of our daily life, from the climate to the existence of daylight and night, and the presence of life on Earth.