Objectives (5 - 7 minutes)

1. Familiarize students with the concept of decimal numbers, more specifically with decimal fractions of tenths and hundredths.
2. Teach students the decimal representation of these fractions, using the system of dots and commas.
3. Develop students' ability to identify and compare decimal numbers, allowing them to understand the order in decimal numbers and to make comparisons between them.

Introduction (10 - 12 minutes)

1. Recalling concepts: The teacher starts the lesson by briefly reviewing integers and fractions. He can ask students if they remember what fractions are and if they have seen fractions with denominators of 10 or 100. The teacher can use practical examples, such as dividing a pizza into 10 equal slices, to help students understand the concept.

2. Problem situations: The teacher then presents two problem situations that will be solved during the lesson. The first one could be: "If we have a chocolate bar and divide it into 10 equal parts, how much does each part represent of the bar?". The second one could be: "And if we divide the same chocolate bar into 100 equal parts, how much will each part represent?".

3. Contextualization: The teacher explains that understanding decimal numbers is important in many everyday situations, such as in purchases (0.50 reais is half of 1 real), measurements (1.5 meters is one and a half meters), and in money (0.10 reais is a tenth of one real).

4. Engaging students' attention: The teacher introduces the lesson topic by mentioning that decimal numbers are used not only in mathematics but also in other subjects and even in games. He can mention that in racing games, times are measured in tenths and hundredths of a second. Additionally, in music, notes are divided into smaller parts, called semitones, which are similar to tenths and hundredths.

Development (20 - 25 minutes)

In this stage, students will carry out practical activities that will help them understand and represent decimal numbers of tenths and hundredths. The teacher can choose to do all activities or select the ones that best suit the class.

Activity 1: Dividing the pizza

1. The teacher brings a whole pizza to the classroom, containing 10 slices.
2. Students are divided into small groups, and each group receives a sheet of paper with the shape of the whole pizza.
3. The teacher asks each group to color the number of slices corresponding to a decimal number of tenths (for example, 3/10 or 0.3) and hundredths (such as 4/100 or 0.04).
4. The groups must then represent the decimal number in fraction form and in decimal format (using the system of dots and commas).
5. Finally, the teacher asks the students to compare the fractions and the decimal numbers to develop an understanding of the equivalence between them.

Activity 2: Balls in the box

1. The teacher brings a box containing 100 small balls.
2. Students, again in groups, receive a sheet of paper with the shape of the box.
3. Each group must color the number of balls corresponding to a decimal number of hundredths (for example, 23/100 or 0.23).
4. As in the previous activity, the groups must represent the decimal number in fraction form and in decimal format.
5. Finally, the groups must compare the fractions and the decimal numbers to develop an understanding of the equivalence between them.

Activity 3: Comparing modeling clay

1. The teacher brings two boxes of modeling clay in different colors.
2. Students, in groups, receive two sheets of paper for each box of clay.
3. Each group must divide one of the boxes into 10 equal parts and the other into 100 equal parts.
4. The groups must then color the number of parts corresponding to two decimal numbers given by the teacher.
5. As in the previous activities, the groups must represent the decimal numbers in fraction form and in decimal format and then compare them.

Throughout these activities, the teacher should circulate around the classroom, observing and guiding students as necessary. After completing the activities, the teacher should gather the class for a collective discussion about the solutions found and the strategies used.

Feedback (10 - 15 minutes)

1. Group Discussion: The teacher gathers all students and promotes a group discussion to share the solutions found in each of the activities. He can ask a representative from each group to explain how they represented and compared the decimal numbers. The teacher should encourage students to explain their solutions, ensuring that all students have the opportunity to speak and share their ideas. During the discussion, the teacher can ask questions to stimulate critical thinking and understanding, such as: "Why do you think 0.5 is greater than 0.2?". (5 - 7 minutes)

2. Connection to Theory: After the discussion, the teacher should summarize the main ideas discussed, reinforcing the concept of decimal numbers and their representation of tenths and hundredths. He should relate the solutions found by students to the theory covered in the lesson introduction, showing how the practical activities helped illustrate the concept. For example, the teacher can take one of the drawings made by students in the pizza activity and show how it represents 0.3 or 3/10. (3 - 5 minutes)

3. Reflection on Learning: To conclude the lesson, the teacher proposes that students reflect for a minute on what they have learned. He can ask two simple questions to guide the reflection:

   • "What did you discover about decimal numbers today?"
   • "How can you use what you learned today in everyday situations?".

   The teacher can ask students to share their answers with the class if they feel comfortable. This reflection stage is important to help students consolidate what they have learned and understand the relevance of the topic to their daily lives. (2 - 3 minutes)

Conclusion (5 - 7 minutes)

1. Lesson Summary: The teacher begins the conclusion of the lesson by summarizing the main points covered during the lesson. He reiterates the concept of decimal numbers, specifically tenths and hundredths, and how they are represented in decimal form. The teacher recalls the practical activities carried out, highlighting the solutions found by students and the strategies used to represent and compare decimal numbers.

2. Connection between Theory and Practice: Next, the teacher explains how the lesson connected theory with practice. He emphasizes how the practical activities helped students visualize and understand the concept of decimal numbers. The teacher mentions that by coloring the parts corresponding to the decimal numbers in the pizza, balls box, and modeling clay activities, students were able to concretely see the decimal representation of these numbers.

3. Extra Materials: The teacher then suggests extra materials for students who wish to deepen their knowledge of decimal numbers. He can recommend textbooks, online games, educational videos, and websites with interactive activities on the subject. The teacher can also suggest that students practice at home, with the help of their parents or guardians, dividing objects into equal parts and representing these parts as decimal numbers.

4. Relevance of the Subject: Finally, the teacher explains the importance of the subject for students' daily lives. He mentions that decimal numbers are widely used in everyday situations, such as in purchases, measurements, and money. The teacher can give practical examples, such as: "If you are going to buy a candy that costs 1.50 reais and you have 2 reais, do you have enough money to buy the candy?" or "If you measure a line and it is 2.35 meters, is it larger or smaller than 2 and a half meters?". The teacher reinforces that understanding decimal numbers is important for daily life and for learning mathematics in later years.

This conclusion helps consolidate students' learning, reinforces the relevance of the subject, and encourages them to continue exploring and learning about decimal numbers.