Objectives (5 - 7 minutes)

1. Understand the composition and decomposition of natural numbers less than 10,000: The teacher should explain to the students the concept of composition and decomposition of natural numbers. They should understand that a number can be formed by combining other smaller numbers (composition) and that a number can be separated into smaller parts (decomposition).

2. Identify the different positions of digits in numbers: The teacher should teach students about the positions of digits in a number (units, tens, hundreds, etc.). Students should be able to identify the position of a digit in a number and the value it represents based on its position.

3. Perform the composition and decomposition of natural numbers less than 10,000: Students should be able to apply what they have learned about the composition and decomposition of numbers to solve practical problems. They should be able to assemble and disassemble numbers using different combinations of digits.

Introduction (10 - 12 minutes)

1. Review of previous concepts: The teacher should start the lesson by reviewing the concepts of natural numbers and their importance in our daily lives. Additionally, a brief review of addition and subtraction concepts, which will be fundamental for understanding the composition and decomposition of numbers, should be conducted. (3 - 4 minutes)

2. Problem Situation 1 - The puzzle game: The teacher can propose a puzzle game to introduce the concept of composition and decomposition of numbers. They can bring a puzzle with an image divided into different parts and ask students to observe the separated parts. Then, they can ask: 'If each of these parts were a number, how could we put them together to form a larger number? And if we had a large number, how could we break it down into smaller parts?' (2 - 3 minutes)

3. Problem Situation 2 - The candy store: The teacher can propose a situation where students are in a candy store and want to buy different quantities of candies. The teacher can ask: 'If I want to buy 15 candies, how many tens do I need to buy? And if I want to buy 37 candies, how many tens and how many units do I need to buy?' This exercise will help students understand the importance of the positions of digits in numbers. (3 - 4 minutes)

4. Contextualization - Importance in daily life: The teacher should explain to students how the composition and decomposition of numbers are important in our daily lives. Examples such as counting money, reading time, interpreting phone numbers, among others, can be mentioned. This will help students understand that what they are learning in class has practical and real applications. (2 - 3 minutes)

Development (20 - 25 minutes)

1. Theory - Composition of numbers: The teacher should explain that the composition of numbers is the process of combining different quantities to form a larger number. For example, to compose the number 134, we combine 100, 30, and 4. The importance of the positions of digits should be emphasized: the hundredth (3rd digit from the left to the right), the tenth (2nd digit from the left to the right), and the unit (1st digit from the left to the right). (5 - 7 minutes)

2. Theory - Decomposition of numbers: The teacher should explain that the decomposition of numbers is the process of separating a number into its smaller parts. For example, to decompose the number 134, we separate 100, 30, and 4. The positions of the digits and the value that each position represents should be emphasized again. (5 - 7 minutes)

3. Activity - Composition and Decomposition of numbers: The teacher should propose a series of exercises for students to practice the composition and decomposition of numbers. The exercises can be done together with the students on the board, so that everyone can participate and learn from each other's mistakes and successes. The teacher can start with smaller numbers and, as students gain confidence, increase the difficulty of the numbers. (10 - 12 minutes)

   • Example of exercise for composition: The teacher can ask students: 'How can we compose the number 256?' Students should identify that the number is composed of 200, 50, and 6.

   • Example of exercise for decomposition: The teacher can ask students: 'How can we decompose the number 894?' Students should identify that the number can be decomposed into 800, 90, and 4.

4. Connection - Application of the learned content: The teacher should encourage students to think about everyday situations where the composition and decomposition of numbers can be useful. For example, when counting money, reading an address, interpreting a kitchen recipe, among others. This will help students realize the importance of what they are learning and apply this knowledge outside the classroom. (5 - 6 minutes)

Return (8 - 10 minutes)

1. Group Discussion (3 - 4 minutes): The teacher should promote a group discussion for students to share their answers and solutions to the composition and decomposition activities. The goal is for students to help each other understand the concepts and solve the problems. During the discussion, the teacher should clarify any doubts that may arise and reinforce the concepts that were learned.

2. Theory Review (2 - 3 minutes): After the group discussion, the teacher should review the main points of the theory, reinforcing the concepts of composition and decomposition of numbers and the importance of the positions of digits. The teacher can do this interactively, asking students to explain the concepts in their own words or give examples of situations where these concepts could be applied.

3. Reflection (2 - 3 minutes): Next, the teacher should propose that students reflect on what they learned in the lesson. For this, the teacher can ask two simple questions: (1) 'What was the easiest part of today's lesson and why?' and (2) 'What was the most difficult part of today's lesson and why?' Students should have a minute to reflect on each question before sharing their answers with the class. This reflection step is important for students to evaluate their own learning and recognize the challenges they still need to overcome.

4. Praise and Encouragement (1 minute): Finally, the teacher should praise the efforts of the students and encourage them to continue practicing the composition and decomposition of numbers. The teacher can emphasize that mathematics is a skill that develops with practice and that everyone is capable of learning, as long as they make an effort and believe in themselves.

Conclusion (5 - 7 minutes)

1. Lesson Summary (2 - 3 minutes): The teacher should recap the main points covered during the lesson. This includes the explanation of the composition and decomposition of natural numbers less than 10,000, the importance of the positions of digits in numbers, and the resolution of practical problems involving the composition and decomposition of numbers. The teacher can use examples from the activities carried out during the lesson to illustrate these concepts.

2. Connection between Theory and Practice (1 - 2 minutes): The teacher should highlight how the theory taught in the lesson connects with the practical activities carried out by the students. For example, the teacher can explain how the theory of composition and decomposition of numbers was applied in the activity of solving practical problems. Additionally, the teacher can emphasize how the practice of composition and decomposition of numbers can be useful in everyday situations, such as counting money or reading time.

3. Extra Materials (1 minute): The teacher can suggest some extra materials for students who wish to deepen their knowledge on the subject. This may include textbooks, online games, educational videos, and math websites. The teacher should briefly explain each resource and how it can help students reinforce what they learned in the lesson.

4. Importance of the Subject (1 - 2 minutes): Finally, the teacher should explain the importance of the composition and decomposition of numbers in the broader context of mathematics and everyday life. The teacher can emphasize that the ability to compose and decompose numbers is fundamental for solving more complex mathematical problems. Additionally, the teacher can highlight how this skill is useful in practical situations, such as counting objects, reading numbers on signs and labels, and calculating change in purchases. The teacher should encourage students to practice the composition and decomposition of numbers in their daily activities to strengthen this skill.