Objectives (5 - 10 minutes)

1. Understand the concept of quadrilaterals: The main objective is for students to become familiar with the term 'quadrilaterals' and understand that it is a general term that refers to a flat geometric figure with four sides. Students should be able to identify and name the different types of quadrilaterals (rectangles, squares, trapezoids, etc.) and recognize their distinctive characteristics.

2. Identify the basic properties of each type of quadrilateral: Each type of quadrilateral has its own unique characteristics. Students should learn and be able to identify the basic properties of each type of quadrilateral. For example, a rectangle has four right angles and equal opposite sides, while a trapezoid has only one pair of parallel sides.

3. Differentiate between the different types of quadrilaterals: In addition to identifying the properties of each type of quadrilateral, students should be able to differentiate between the different types. This involves understanding how the properties of one type of quadrilateral may be different from those of another type. For example, students should be able to identify that, although a square and a rectangle have equal opposite sides, only the square has all sides equal.

Secondary Objectives:

• Apply the knowledge learned in practical problems: Students should be able to use the acquired knowledge to solve practical problems involving the identification and classification of quadrilaterals. This may include determining unknown properties based on known properties or classifying a quadrilateral based on its properties.

• Develop critical thinking and problem-solving skills: Through the study of quadrilaterals, students should be encouraged to develop critical thinking and problem-solving skills. They should learn to analyze a problem, identify relevant information, apply the acquired knowledge, and arrive at a solution.

The Objectives should be communicated to the students at the beginning of the lesson so that they know what to expect and what is expected of them by the end of the lesson.

Introduction (10 - 15 minutes)

1. Review of previous concepts: The teacher should start by reviewing the basic concepts of plane geometry, such as line segments, angles, and polygons. It is important for students to remember these concepts as they will be the basis for understanding quadrilaterals. (3 - 5 minutes)

2. Presentation of problem situations: Next, the teacher can present two problem situations that will serve as a trigger for the Introduction of the topic. For example, students can be asked how they would classify an object that has four sides, but its sides are not all equal. Another question could be about how they would classify an object with four sides and four right angles. These questions should be designed to arouse students' curiosity and get them thinking about the topic of the lesson. (4 - 5 minutes)

3. Contextualization: Next, the teacher should explain the importance of quadrilaterals in everyday life. For example, they may mention that quadrilaterals are widely used in architecture and engineering to design structures and buildings. They may also mention that quadrilaterals appear in many everyday objects, such as books (which are rectangles), computer monitors (which are squares or rectangles), and street signs (which are trapezoids). (2 - 3 minutes)

4. Introduction to the topic: Finally, the teacher should introduce the topic of quadrilaterals. They can define what quadrilaterals are, mention that there are different types of quadrilaterals, and that each has its own unique properties. The teacher can use images or drawings on the board to illustrate these concepts. (2 - 3 minutes)

This step is crucial to capture students' attention and prepare them for the content that will be covered in the lesson. By the end of the Introduction, students should be curious and motivated to learn more about quadrilaterals.

Development (20 - 25 minutes)

1. Activity 'Classifying Quadrilaterals' (10 - 15 minutes)

   • Description: The teacher will divide the class into groups of up to 5 students. Each group will receive a set of cards, each containing the visual representation of a quadrilateral and a brief description of its characteristics. The quadrilaterals will include rectangles, squares, parallelograms, trapezoids, and rhombuses. The description on each card will intentionally be incomplete, missing one or two main properties that the students should identify.
   • Step by step:
     1. The teacher will distribute the cards and explain the activity.
     2. The students, in their respective groups, should analyze each card, discuss the characteristics of the represented quadrilateral, and try to identify the missing property.
     3. After a set time, each group will present one of their cards to the class, explaining which type of quadrilateral it refers to and what the missing property is.
     4. The teacher will then provide the correct answer and explain the missing property.

2. Activity 'Building Quadrilaterals' (10 - 15 minutes)

   • Description: Still in their groups, students will receive a sheet of paper, a ruler, and a compass. They should use these materials to construct the five types of quadrilaterals that were studied (rectangle, square, parallelogram, trapezoid, and rhombus).
   • Step by step:
     1. The teacher will provide a demonstration of how to use the ruler and compass to construct each type of quadrilateral.
     2. Then, the students, in their groups, will try to construct each type of quadrilateral. The teacher and assistant will circulate around the room, providing guidance and clarifying doubts as needed.
     3. After all groups have constructed all the quadrilaterals, they will be invited to compare the constructions of their quadrilaterals and discuss any differences or similarities they observe.
     4. The teacher will then lead a class discussion, highlighting the visual properties of each type of quadrilateral and how they relate to the definitions and properties discussed in the Introduction of the lesson.

These activities encourage collaboration among students, promote discussion and critical thinking, and allow students to apply what they have learned in a practical way. Additionally, the activity of constructing quadrilaterals helps solidify students' understanding of the visual properties of each type of quadrilateral.

Return (10 - 15 minutes)

1. Group Discussion: (5 - 7 minutes)

   • Description: The teacher should gather all students in a circle for a group discussion. Each group will have the opportunity to share their solutions or conclusions from the previous activities. The teacher should encourage students to explain the reasoning behind their answers and to ask each other questions. The teacher should also take the opportunity to clarify any concepts that have not yet been understood by the students.
   • Step by step:
     1. The teacher gathers all students in a circle.
     2. Then, a representative from each group is invited to briefly share their solutions or conclusions from the previous activities.
     3. Other students are encouraged to ask questions and offer constructive feedback.
     4. The teacher uses the discussion to reinforce key concepts and clarify any misunderstandings.

2. Connection to Theory: (3 - 5 minutes)

   • Description: After the group discussion, the teacher should revisit the theoretical concepts presented at the beginning of the lesson and show how they apply to the practical activities carried out.
   • Step by step:
     1. The teacher briefly reviews the theoretical concepts of quadrilaterals and their properties, highlighting the distinctive characteristics of each type of quadrilateral.
     2. Then, the teacher shows how these concepts were applied in the practical activities, reinforcing the idea that theory and practice are interconnected and complement each other.
     3. The teacher can also highlight any difficulties or challenges that students faced during the activities and discuss how these challenges were overcome.

3. Final Reflection: (2 - 3 minutes)

   • Description: To conclude the lesson, the teacher should propose that students reflect individually on what they have learned. The teacher can do this by asking questions such as 'What was the most important concept you learned today?' and 'What questions have not been answered yet?'.
   • Step by step:
     1. The teacher poses the reflection questions and gives students a minute to think about their answers.
     2. Then, some students are invited to share their answers with the class.
     3. The teacher ends the lesson by reinforcing the importance of the topic studied and encouraging students to continue exploring the subject on their own.

This Return stage is crucial for consolidating students' learning, allowing them to reflect on what they have learned, make connections with theory, and apply the knowledge they have gained. Additionally, the group discussion provides a valuable opportunity for students to learn from each other and for the teacher to assess the class's understanding of the topic.

Conclusion (5 - 10 minutes)

1. Content Summary: The teacher should begin the Conclusion by summarizing the main points covered during the lesson. This includes the definition of quadrilaterals, the identification and classification of different types of quadrilaterals (rectangles, squares, parallelograms, trapezoids, and rhombuses), and the unique properties of each of them. The teacher can use the board or a slide to visually summarize these points. (2 - 3 minutes)

2. Connection between Theory, Practice, and Applications: Next, the teacher should highlight how the lesson connected the theory, practice, and applications of quadrilaterals. The teacher can emphasize how the theory (for example, the definitions and properties of quadrilaterals) was applied in practice (through the activities of classifying and constructing quadrilaterals) and how the applications of quadrilaterals were discussed in relation to students' everyday lives. (1 - 2 minutes)

3. Extra Materials: The teacher can then suggest extra materials for students who wish to deepen their understanding of the topic. This may include additional readings, explanatory videos, online geometry games, or quadrilateral problems to solve. The teacher can provide a list of these resources on the board, on the school's website, or send them by email to the students. (1 - 2 minutes)

4. Relevance of the Topic: Finally, the teacher should summarize the importance of studying quadrilaterals. They may reiterate that quadrilaterals are common figures in everyday life, found in many structures, objects, and designs around us. The teacher may also mention that the ability to identify and classify quadrilaterals is useful in many areas, such as architecture, design, engineering, sciences, and even in games and puzzles. (1 - 2 minutes)

This Conclusion stage is essential for consolidating students' learning, reinforcing the relevance of the topic, and encouraging continued study. By the end of the lesson, students should have a clear and comprehensive understanding of quadrilateral concepts and be able to apply this knowledge in practical situations.