Context

Decimal numbers are a way to express non-integer numbers, and understanding them is essential for dealing with fractional quantities. They are used to represent quantities such as length, capacity, and mass, among others. The decimal system is used worldwide and serves as the basis for more complex mathematical operations, such as operations with fractions, ratios, proportions, and percentages.

Understanding the decimal system involves grasping the position of the digits, where each position has a weight value ten times greater than the position to its right and ten times smaller than the position to its left. For example, in the number 123.4, each digit has a different value depending on its position: '1' represents one hundred (100), '2' represents twenty (20), '3' represents three (3), and the '4' after the decimal point represents four tenths (0.4).

Learning decimal numbers is relevant for everyday life, as they are present in numerous daily situations. For example, when checking the price of a product at the supermarket, refueling the car, calculating grades in school, or even measuring ingredients for a recipe. Without the use of decimal numbers, it would be very difficult to deal with many of these scenarios.

Furthermore, the study of decimal numbers is also very important for various professional fields, including engineering, architecture, physics, medicine, among others. They are essential for the mathematical operations required in these professions.

Students can delve deeper into this topic by accessing the following resources:

1. Decimal Numbers - Khan Academy: https://www.khanacademy.org/math/arithmetic/arith-decimals
2. Decimal Numbers - Mundo Educação: https://mundoeducacao.uol.com.br/matematica/numeros-decimais.htm
3. Decimal Numbers - Matemática Rio with Prof. Rafael Procópio - YouTube: https://www.youtube.com/watch?v=Vjv4Z39l8HE

Practical Activity: 'Discovering the World of Decimals'

Project Objective

This project aims to provide students with a practical understanding and real-world application of decimal numbers through an interactive game.

Project Description

Students will be divided into groups of 3 to 5 and will develop a board game where each move involves solving problems that use decimal numbers.

Required Materials

1. A large piece of cardboard or poster board to create the game board.
2. Colored cards to write the questions and answers.
3. Small pieces to mark the players' positions on the board (can be anything small that students have like buttons, coins, bottle caps, etc).
4. Colored pens to decorate and write on the board and cards.
5. Ruler or measuring tape.
6. Die or a mobile app that simulates rolling a die.

Project Step-by-Step

1. Together, students should create a game board with a path leading from a starting point to a finish point. This path should be divided into various spaces.

2. On each space, students should write a mathematical operation involving decimal numbers or create a question that involves the use of decimal numbers. Example: 'If John has 3.5 candies and Mary has 2.2 candies, how many candies do they have together?'.

3. The answers to each question should be written on separate colored cards.

4. Students roll the die and move their piece according to the number rolled. When landing on a space, they must solve the proposed problem. If they answer correctly, they continue playing normally in the next round. If they answer incorrectly, they lose their next turn.

5. The first to reach the end of the board wins the game.

6. Students should test the game to adjust the difficulty of the questions and the size of the board so that the game duration is balanced.

After completing the project, each group should prepare a report with the following topics:

1. Introduction: Students should discuss the concept of decimal numbers, their importance and real-world application, and the objective of the project they carried out. They should contextualize the use of decimal numbers in everyday situations.

2. Development: They should describe the logical process they followed to create the board and the problems. They should explain the execution of the game and any difficulties encountered during the practice. It is interesting for them to explain how the moves were, which questions were the most difficult, and how they performed in them.

3. Conclusions: Students should reflect on what they learned, how they felt working in a group, and how the experience of applying knowledge in decimal numbers in a playful way was. They should consider any difficulties they had and how they overcame them.

4. Bibliography: Students should list the materials they used to study decimal numbers. It can be the textbook, websites, YouTube videos, or any other material that contributed to the project.

In this way, in addition to learning about decimal numbers, students will develop important skills such as teamwork, problem-solving, logical thinking, creativity, among others.