Objectives (5 - 7 minutes)

1. Understand the concept of enlargement and reduction of figures: Students should be able to identify and define the process of enlargement and reduction of geometric figures, understanding how they change in size but maintain the same shape and proportion.

2. Apply enlargement and reduction in practical situations: This skill involves the ability to use the concept of enlargement and reduction in real-world contexts, such as maps, house plans, and architectural models, to solve problems and make predictions.

3. Analyze the relationship between enlargement and reduction and proportions: Students should be able to perceive how the enlargement or reduction factor affects the proportions of a figure, allowing them to make predictions and accurate calculations.

Secondary Objectives:

• Develop critical thinking and problem-solving skills by applying the concept of enlargement and reduction in practical situations.
• Promote collaboration and effective communication among students, encouraging them to discuss and share their strategies and solutions.

Introduction (10 - 15 minutes)

1. Review of previous concepts: The teacher should start by reviewing previous mathematical concepts that are fundamental to understanding the lesson topic. This may involve a quick recap of concepts such as proportion, ratio, and the use of scales. The teacher may ask questions to check students' understanding and clarify any remaining doubts.

2. Problem situation: The teacher can present students with two problem situations to arouse interest and curiosity about the topics that will be covered in the lesson. For example, the teacher can show an enlarged map of a city and ask how the same city would look in a reduced scale. Another situation may involve building a scale model of a house, where students must determine the correct proportions for the model's reduction or enlargement.

3. Contextualization of the subject: The teacher can then explain the importance of the concept of enlargement and reduction of figures in different areas of real life. This may include its use in architecture and engineering for building models and house plans, in cartography for map creation, and even in art for creating replicas of artworks in different sizes.

4. Introduction of the topic: To capture students' attention, the teacher can share some curiosities or interesting applications of the topic. For example, the teacher may mention that the concept of enlargement and reduction of figures is used in film production to create special effects, such as shrinking a character to appear small in a giant world. Another curiosity may be that enlargement and reduction of figures are used in medicine to create life-size models of organs for study and surgical practice.

Development (20 - 25 minutes)

1. Theory presentation (10 - 12 minutes):

   • Definition of enlargement and reduction: The teacher should start by defining the terms 'enlargement' and 'reduction' in the context of geometry. Enlargement refers to increasing the size of a figure while maintaining the same proportion between its elements. Reduction, on the other hand, is decreasing the size of a figure while maintaining the same proportion between its elements.
   • Properties of enlargement and reduction: The teacher should explain that when enlarging or reducing a figure, all its sides and angles are multiplied by the same factor. That is, if a figure is enlarged or reduced by a factor of 3, then all its sides and angles will be multiplied by 3.
   • Scales: The teacher should introduce the concept of scale, which is the ratio between the dimensions of an object in the model and the corresponding dimensions of the real object. This can be exemplified with the idea of a map, where the scale indicates how many times the real world has been reduced to fit on paper.
   • Enlargement and reduction factor: The teacher should explain that the enlargement or reduction factor is the ratio between the size of the enlarged or reduced figure and the size of the original figure. This can be illustrated with examples, such as enlarging or reducing a photo in an image editor.

2. Problem solving (10 - 13 minutes):

   • Practical examples: The teacher should present practical examples of situations that require the application of the concept of enlargement and reduction. This may include map problems, where students must determine the scale or distance on an enlarged or reduced map. Another example may involve building scale models, where students must determine the correct proportions for the enlargement or reduction of the model.
   • Step-by-step resolution: The teacher should guide students through the process of solving these problems, emphasizing the importance of identifying the enlargement or reduction factor and applying it correctly. The teacher should encourage students to think critically and discuss their strategies and solutions.
   • Feedback and clarification of doubts: The teacher should provide feedback to students on their answers and clarify any doubts that may have arisen during the problem-solving.

3. Practical activity (5 - 10 minutes):

   • Application of theory: The teacher should propose a practical activity where students will have to apply what they have learned about enlargement and reduction of figures. This may involve building a scale model of a house, creating an enlarged map of a local area, or enlarging or reducing a photo using an image editor.
   • Discussion and reflection: After the activity, the teacher should encourage students to discuss what they have learned and how they applied the concept of enlargement and reduction. This may include a discussion of the challenges they faced and the strategies they used to overcome them.

Return (8 - 10 minutes)

1. Concept review (3 - 4 minutes): The teacher should start this stage by reviewing the main concepts covered during the lesson. This may involve a quick recap of the terms 'enlargement', 'reduction', 'scale', and 'enlargement or reduction factor', and the importance of maintaining the proportion between the elements of the figure when enlarging or reducing. The teacher may ask students questions to check understanding and clarify any remaining doubts.

2. Connection to practice (2 - 3 minutes): The teacher should then ask students to reflect on how the theory connects to the practical activities carried out during the lesson. This may involve asking students how they applied the concept of enlargement and reduction when building the scale model, creating the enlarged or reduced map, or enlarging or reducing the photo. The teacher should encourage students to provide specific examples and explain the reasoning behind their answers.

3. Final reflection (2 - 3 minutes): The teacher should then propose that students reflect for a minute on the following questions:

   1. What was the most important concept you learned today?
   2. What questions have not been answered yet?
   3. How can you apply what you learned today in everyday situations?

4. Sharing reflections (1 minute): The teacher should ask some students to share their answers with the class. This can offer an opportunity for students to learn from each other, see different perspectives, and discover new applications for what they have learned.

5. Feedback and closure (1 minute): The teacher should thank the students for their participation and hard work during the lesson. The teacher can then provide general feedback on the lesson and answer any final questions. The teacher should also inform students about what will be covered in the next lesson and any materials that may be needed.

Conclusion (5 - 7 minutes)

1. Summary of contents (2 - 3 minutes): The teacher should start the conclusion of the lesson by summarizing the main points covered. This may involve a quick recap of the concepts of enlargement and reduction, the idea of maintaining the proportion between the elements of the figure during this process, the definition of scale, and the enlargement or reduction factor. The teacher can reinforce these concepts through practical examples and questions to check students' understanding.

2. Connections between theory, practice, and applications (1 minute): Next, the teacher should highlight how the lesson connected theory, practice, and applications. The teacher should recall the practical activities carried out and how they illustrated the application of the concept of enlargement and reduction. The teacher may also mention again the applications of the concept in different real-life contexts, reinforcing the relevance of what was learned.

3. Extra materials (1 - 2 minutes): The teacher should then suggest some extra materials for students who wish to deepen their knowledge on the topic. This may include math books, online learning websites, explanatory videos, interactive math games, among others. The teacher can provide a list of these resources for students to consult in their own time.

4. Relevance of the topic (1 minute): Finally, the teacher should emphasize the importance of the topic for students' daily lives. The teacher can recall the practical applications of the concept of enlargement and reduction, such as in maps, house plans, architectural models, and even in unexpected areas like cinema and medicine. The teacher should encourage students to continue seeking examples of the use of this concept in their everyday environment to reinforce learning and understanding of the topic.

5. Closure (1 minute): The teacher should thank the students for their participation and effort during the lesson. The teacher should encourage students to bring any questions or doubts to the next lesson and reinforce the importance of continuous practice and review for the consolidation of the concepts learned.