Objectives (5 - 10 minutes)

1. Make students understand the concept of units of capacity and mass measurement, and be able to distinguish between the standard units (liter and kilogram) and their subdivisions (milliliter and gram).

2. Develop students' ability to make estimates and measurements of capacity and mass using appropriate units of measurement, with the support of didactic materials and basic measuring instruments (cup, scale, spoon, etc.).

3. Encourage students to apply the acquired knowledge in practical everyday situations, such as measuring liquids for recipes, comparing object weights, among others.

Secondary objectives:

• Promote interaction among students through group learning activities, stimulating respect and collaboration.

• Stimulate critical thinking and problem-solving through activities involving the practical application of learned concepts.

Introduction (10 - 15 minutes)

1. Recalling previous contents: The teacher starts the lesson by reminding students about the concept of measurements and the importance of knowing how to measure things in our daily lives. He can bring simple examples, such as measuring a classmate's height, the amount of water in a glass, or the weight of an object.

2. Problem situations: The teacher proposes two problem situations to arouse students' curiosity and interest. The first one is: 'Imagine we are making a cake and need to know how much milk to use. How can we measure that?'. The second one is: 'If we want to know the weight of an apple, how can we do that?'.

3. Contextualization: The teacher explains that the answers to these problem situations are related to the units of capacity and mass measurement, which will be the focus of the lesson. He can contextualize by saying that these measurements are widely used at home, in the kitchen, and in many other daily life situations.

4. Capturing students' attention: To capture students' attention, the teacher can share some curiosities. For example, he can say that the liter of milk we use at home is a unit of capacity measurement, and that the kilogram of rice we buy at the supermarket is a unit of mass measurement. He can also show everyday objects representing these measurements, such as a 1-liter water bottle and a 500-gram pack of pasta.

5. Introduction to the topic: Finally, the teacher introduces the topic of the lesson, saying that they will learn more about the units of capacity and mass measurement, and how to use them to measure liquids and solids. He explains that these measurements are very important and used in many situations, such as in the kitchen, in building construction, in transporting goods, among others.

Development (20 - 25 minutes)

Here are three activity suggestions to be carried out in the classroom during the lesson development stage. The teacher can choose one or more activities, depending on the pace and interest of the students. Each activity is designed to be interactive, practical, and fun, and to reinforce the concepts of capacity and mass. The teacher should facilitate the activity, guiding the students and clarifying doubts as necessary.

1. 'Mathematical Firefighters' (10 - 15 minutes)

   • The teacher divides the class into small groups, and each group receives a quantity of empty cups of different sizes, a jug of water, and a scale.
   • The group's task is to fill the cups with water in a way to have the highest and lowest weight possible, without exceeding the cups' limits.
   • Before starting the activity, the teacher should explain that they are acting as 'mathematical firefighters' and need to fill the cups with a specific amount of water to fight a fire.
   • Students should estimate and then measure the amount of water in the cups using the scale. They should record the amount of water in grams.

2. 'Mathematical Recipe' (10 - 15 minutes)

   • The teacher prepares some simple 'recipes' for juices or smoothies, where the quantity of each ingredient is given in milliliters.
   • Students are divided into small groups, and each group receives a different 'recipe', along with the ingredients and measuring utensils (measuring cups, spoons, etc.).
   • The group's task is to follow the 'recipe', correctly measuring the quantity of each ingredient in milliliters.
   • Before starting the activity, the teacher should explain that they are acting as 'chefs' and need to accurately measure the ingredients to make a delicious juice or smoothie.
   • Students should estimate and then measure the quantity of each ingredient using the measuring utensils. They should record the quantity of each ingredient in milliliters.

3. 'Measurement Treasure Hunt' (10 - 15 minutes)

   • The teacher hides several objects around the classroom, and each object has a card showing the unit of mass (grams or kilograms) or capacity (milliliters or liters) that the students must find.
   • Divided into teams, students have to search for the objects and record on the card if they believe the object is measured in grams, kilograms, milliliters, or liters.
   • After all objects are found, the teacher measures and weighs the objects, and students check if their estimates were correct.

The teacher can choose the activity that best suits the class and ensure that the necessary materials are ready before the lesson. During the activities, the teacher should move around the groups, providing support and clarifying doubts as needed.

Feedback (10 - 15 minutes)

1. Group Discussion (5 - 7 minutes)

   • The teacher gathers all students and promotes a group discussion about the solutions found and the conclusions of each activity.
   • Each group will have the opportunity to share their discoveries, challenges, and learnings with the rest of the class, encouraging the exchange of experiences and collaborative learning.
   • The teacher can ask guiding questions, such as: 'How did you decide how much water to put in the cup?', 'Did you encounter any difficulties when measuring the recipe ingredients? How did you solve it?' and 'Did you find it easy or difficult to estimate the measurements of the objects in the measurement treasure hunt?'.

2. Connection with Theory (3 - 5 minutes)

   • After the discussion, the teacher will connect the practical activities carried out with the theory presented at the beginning of the lesson, reinforcing the concepts of capacity and mass and their units of measurement.
   • For example, the teacher can ask: 'In the 'Mathematical Firefighters' activity, what did the cup's capacity represent?', 'In the 'Mathematical Recipe' activity, which unit of measurement did you use to measure the ingredients?' and 'In the 'Measurement Treasure Hunt', which unit of measurement did you use to measure the objects?'.

3. Individual Reflection (2 - 3 minutes)

   • To conclude the lesson, the teacher proposes that students reflect individually on what they have learned. He can ask two simple questions to guide students' reflection:
     1. 'What was the most interesting part of today's lesson and why?'
     2. 'How can you use what you learned today in situations in your daily life?'
   • The teacher can ask students to share their answers with the class, if they feel comfortable, or simply reflect silently.
   • This reflection stage helps students consolidate what they have learned, realize the relevance of the concepts presented, and value their own learning process.

The teacher should ensure that the discussion and reflection environment is respectful and welcoming, encouraging all students to participate and express their opinions. He should also take this opportunity to assess students' understanding of the topic and identify possible learning gaps that need to be addressed in the future.

Conclusion (5 - 7 minutes)

1. Review of Contents (2 - 3 minutes)

   • The teacher starts the conclusion of the lesson by recapping the main points covered. He reminds students about the units of capacity measurement (liter and milliliter) and mass (kilogram and gram) and how they are used to measure liquids and solids.
   • The teacher also reinforces the importance of the concept of estimation and how it can be useful in daily life, for example, to calculate ingredient quantities in a recipe or to have an approximate idea of an object's weight.

2. Connection of Theory with Practice (1 - 2 minutes)

   • Next, the teacher highlights how the lesson connected theory with practice. He comments that through the activities, students were able to apply the learned concepts in real situations, such as measuring the amount of water in a cup, weighing objects, or following a recipe.
   • The teacher also emphasizes that by estimating measurements and comparing them with actual measurements, students were able to see the importance of precision in measurements and how small differences can make a big difference in the final result.

3. Extra Materials (1 - 2 minutes)

   • The teacher suggests some extra activities for students to deepen their understanding of the subject. This may include searching for objects at home or at school that have capacity or mass measurements, preparing simple recipes at home using the learned units of measurement, or creating a 'measurement museum' in the classroom with objects of different weights and volumes.
   • The teacher can also recommend some online resources, such as interactive games or educational videos, that address the topic of capacity and mass measurements.

4. Importance of the Subject (1 - 2 minutes)

   • Finally, the teacher concludes the lesson by explaining the importance of the subject for students' daily lives. He reinforces that capacity and mass measurements are used in many everyday situations, from cooking and shopping at the supermarket to building and measuring objects.
   • The teacher also emphasizes that understanding and being able to use these measurements correctly is a valuable skill that can help students be more independent and efficient in their daily tasks. He encourages students to continue exploring and practicing measurements at home and at school.

Throughout the entire conclusion, the teacher should ensure that students have understood the presented concepts and are satisfied with the activities carried out. He should be open to answering any questions or concerns from students and reinforce that learning is a continuous process that requires practice and effort.