Contextualization

Mathematics is the language that allows us to describe and understand the world around us, and one of the most common practical aspects in which we apply it daily is in calculating change. The ability to calculate change correctly is essential for our daily activities, such as buying school snacks, paying for transportation, buying a gift, among others.

Calculating change is a skill that involves two key mathematical concepts: subtraction and understanding the monetary system. Subtraction is the mathematical operation that determines the difference between two numbers. When you pay for an item in a store with more money than the cost of the item, you need to calculate how much money you will get back - this requires subtraction. Additionally, it is necessary to have a solid understanding of the monetary system, including understanding the value of different coins and bills.

Importance of Calculating Change

By understanding and mastering the skill of calculating change, students not only gain confidence in handling money but also learn the importance of financial responsibility. Exercising these skills in a classroom environment allows for safe mistakes and learning before being applied in the real world.

Furthermore, the ability to calculate change also teaches about clarity and fairness. Students learn that they should receive the exact amount of change, and this prepares them to ensure they are not taken advantage of in real life.

Practical Activity: The Right Change Shop

Project Objective

In this practical activity, students will create and manage a "Right Change Shop," where the goal is to practice calculating change in everyday buying and selling situations.

Detailed Project Description

Groups of 3 to 5 students will plan and implement a fictional toy store. The store's products will be created by the students themselves from recyclable materials. Each item for sale in the store will have a price, and students will have to simulate purchases, giving and receiving the correct change. For this, they will use play money.

During the activity, students will take on the roles of seller and buyer. The seller must list the prices of each item, and the buyer must decide what to buy based on a certain amount of fictional money they have available. At the end of the purchase, the seller must calculate the change amount, if any.

The activity should have a total duration of approximately 10 hours, divided over the month for store preparation, price setting, conducting purchase and sale simulations, and preparing the final report.

Necessary Materials

The following materials are needed for the activity:

• Recyclable materials for making store items (cardboard boxes, old magazines, bottle caps, etc.)
• Play money (printed or drawn by the students)
• Paper and pens to list prices
• Notebook or paper for preparing the report.

Detailed Step-by-Step

1. Definition of items and prices: Each group should choose 5 to 10 items to be sold in the store and set a price for each one.
2. Store setup: Using recyclable materials, each group should set up their store, displaying the items for sale with their respective visible prices.
3. Purchase and sale simulation: Students should take on the roles of seller and buyer, conducting several purchase simulations with different change amounts.
   • For example, if an item costs R$ 7 and the buyer pays with a R$ 10 bill, the seller must correctly calculate and give the change of R$ 3.
4. Report preparation: After conducting the simulations, each group should prepare a report documenting the planning and execution process of the activity, as well as the lessons learned.

Project Deliverables

At the end of the project, each group must submit a report with the following structure:

1. Introduction: Contextualize what the activity is, why it is relevant, and what your group's objective was in this project.
2. Development: In this section, detail the theory about calculating change, how the activity was planned and carried out, the methodology used, and the results of the sales simulations. Discuss any difficulties encountered and how they were overcome.
3. Conclusion:
   • Recap the main points of the store planning and execution experience;
   • Explain the lessons learned on how to calculate change and its impact on daily life;
   • Share what each group member learned from the experience, including technical and socio-emotional aspects.
4. Bibliography: List all the information sources used for the project, if any.

Don't forget: the report should be clear, well-structured, and with appropriate language. Take this opportunity to show everything you have learned!