Objectives (5 - 10 minutes)

1. Understand the concept of refractive index: Students should be able to define the refractive index and understand how it affects the speed of light in different media. Additionally, they should understand that the refractive index is a characteristic property of each material.

2. Calculate the angle of refraction: Students should be able to apply Snell's law to calculate the angle of refraction when light passes from one medium to another. They should understand that the refractive index is the ratio between the sine of the angle of incidence and the sine of the angle of refraction.

3. Apply the concept of refractive index in real-life situations: Students should be able to apply the acquired knowledge to solve practical problems. They should be able to interpret the refractive index of a material and use this information to predict how light will behave when passing from one medium to another.

Secondary Objectives:

• Develop critical thinking and problem-solving skills: Through problem-solving related to the refractive index, students should be able to develop essential critical thinking and problem-solving skills.
• Promote active learning and group collaboration: Through the use of the inverted classroom model and group activities, students are encouraged to actively engage in the learning process and collaborate with each other to solve problems.

Introduction (10 - 15 minutes)

1. Review of previous content: The teacher starts the lesson by reminding students of the concepts of light reflection, Snell's law, and the refractive index of air. This review is important to ensure that all students are on the same page and ready to learn about the refractive index in other media. (3 - 5 minutes)

2. Problem-solving situations: The teacher presents two situations involving the refractive index. The first situation may be about sunlight appearing to bend when passing through a window. The second may be about a fish appearing to be in a different place when viewed from outside the water. The teacher asks students to think about what may be happening in each situation and how the refractive index may be involved. (5 - 7 minutes)

3. Contextualization: The teacher explains that the refractive index is a fundamental concept in optics and is used in various real-world applications. For example, the refractive index is used in the manufacturing of lenses for glasses, cameras, and microscopes. Additionally, it is an essential concept in understanding natural phenomena such as rainbows and mirages. (2 - 3 minutes)

4. Capturing students' attention: To spark students' interest, the teacher shares two curiosities about the refractive index. The first is that the refractive index of diamond is so high that light is totally internally reflected within it, causing the characteristic sparkle of a diamond. The second curiosity is that the speed of light in a medium is inversely proportional to its refractive index, which means that light travels slower in denser media. This is what causes light refraction. (1 - 2 minutes)

Development (20 - 25 minutes)

1. Modeling Activity with Refractive Indices (10 - 12 minutes):

   • Scenario: The teacher divides the class into groups of 3 to 4 students. Each group receives a kit containing a transparent container (such as a glass), water, vegetable oil, and a small flashlight.

   • Task: The goal is for students to use the kit materials to model the passage of light through different media (air, water, and oil) and observe how light behaves in each of them. To do this, they should fill the container with water, add some oil, and then shine the flashlight through the container. They should observe how light bends when passing from water to oil and vice versa.

   • Discussion: After completing the activity, the groups should discuss their observations and try to explain what happened. The teacher should guide them to use the concepts of refractive index and Snell's law to explain the observed phenomena.

2. Board Game Activity (10 - 12 minutes):

   • Scenario: The teacher presents students with a pre-prepared board game called 'Journey of Light'. The board contains different types of terrains (representing different media) and obstacles (representing abrupt changes in the refractive index). Each team receives a set of pieces (representing a beam of light) and a die.

   • Task: The goal of the game is for teams to guide their beam of light through the board, following the rules of light refraction. Each time the beam of light passes through a different terrain, the team must calculate the new angle of refraction. If the beam of light hits an obstacle, the team must solve a problem related to the refractive index to decide whether the beam of light is reflected or refracted.

   • Discussion: During the game, the teacher should move around the room, observing the teams and providing guidance as needed. At the end of the game, the teacher should lead a discussion about the strategies used by the teams and the challenges they faced. The teacher should emphasize the importance of correctly calculating the refractive index and the angle of refraction for success in the game.

3. Discussion Activity (5 - 8 minutes):

   • Scenario: The teacher presents students with some everyday situations involving the refractive index, such as the functioning of sunglasses, camera lenses, and microscopes, the formation of rainbows and mirages, among others.

   • Task: Students, still in groups, should discuss how the refractive index is involved in each of the presented situations. They should try to explain the phenomena using the concepts learned in class.

   • Discussion: The teacher should facilitate a whole-class discussion, where each group shares their ideas and conclusions. The teacher should clarify any misunderstandings and reinforce the fundamental concepts related to the refractive index.

These activities are designed to actively engage students in the learning process, allowing them to explore and discover the concepts of refractive index in a practical and fun way. Additionally, they promote group collaboration and the development of essential critical thinking and problem-solving skills.

Return (10 - 15 minutes)

1. Group Discussion (3 - 5 minutes): The teacher gathers all students and asks each group to share the solutions or conclusions they reached during the activities. Each group will have a maximum of 3 minutes to present. During the presentations, the teacher should encourage other students to ask questions and make comments, thus promoting the exchange of ideas.

2. Connection with Theory (3 - 5 minutes): After all presentations, the teacher should provide a general review, connecting the practical activities carried out with the theory presented at the beginning of the lesson. The teacher should explain how the experiments and games helped illustrate the theoretical concepts and better understand the refractive index.

3. Individual Reflection (3 - 5 minutes): The teacher proposes that students reflect individually on what they learned in the lesson. They should think about the following questions:

   • What was the most important concept learned today?
   • What questions have not been answered yet?

   The teacher should give a minute for students to think about their answers. Then, the teacher can ask some students to share their reflections with the class. This not only helps the teacher assess the effectiveness of the lesson but also gives students the opportunity to express their remaining doubts or difficulties.

4. Feedback and Closure (1 - 2 minutes): The teacher concludes the lesson by asking for quick feedback from students about the lesson. He may ask if students found the activities interesting and helpful in understanding the refractive index. The teacher should also take this opportunity to clarify any final doubts and briefly inform about the content of the next lesson.

This Return is a crucial stage of the lesson plan, as it allows the teacher to assess the level of understanding of students and identify any gaps in learning. Additionally, by asking for feedback from students, the teacher demonstrates that he values their opinions and is open to continuously improving his teaching practices.

Conclusion (5 - 10 minutes)

1. Summary of Contents (2 - 3 minutes): The teacher should start the Conclusion phase by summarizing the main points covered during the lesson. He should review the concepts of refractive index, Snell's law, and how to calculate the angle of refraction. The teacher should highlight the practical applications of these concepts and how they are essential to understand various optical phenomena.

2. Connection between Theory, Practice, and Applications (1 - 2 minutes): Next, the teacher should explain how the lesson connected theory, practice, and applications. He should emphasize how the practical activities, such as modeling with refractive indices and the board game, allowed students to visualize and experience the theoretical concepts. The teacher should stress that theoretical understanding is essential, but that practical application and connection with the real world make learning more meaningful.

3. Extra Materials (1 - 2 minutes): The teacher should suggest extra materials for students who wish to explore more about the refractive index. These materials may include explanatory videos, online simulations, additional problems on refractive index resolution, among others. For example, the teacher may suggest the use of an optics simulation app so that students can experience different refraction situations.

4. Relevance of the Refractive Index (1 - 2 minutes): Finally, the teacher should emphasize the importance of the refractive index in everyday life. He may mention again some practical applications, such as the functioning of lenses in glasses and cameras, and natural phenomena, such as the formation of rainbows. The teacher should emphasize that the refractive index is one of the most important optical properties and that understanding how it works is fundamental to understand and appreciate the world around us.

The Conclusion phase is vital to consolidate students' learning and to encourage them to continue studying the topic on their own. Additionally, by highlighting the relevance of the refractive index, the teacher shows students that Physics is not just a set of equations and laws, but a science that helps us understand and appreciate the world around us.