Contextualization

Change is a fundamental concept in our daily lives. Whenever we pay for a product or service with cash, we usually need to receive change. If we pay with a bill of a higher value than the value of the product or service we are buying, the seller must return the excess. That is the change.

In mathematics, change is an important example of a subtraction problem. If we have $10 and buy a magazine for $7, we need to subtract 7 from 10 to calculate our change. In this case, we would have a change of $3.

In addition, change teaches us about the value of coins and bills. When receiving change, we need to understand the value of each coin or bill to ensure that we are receiving the correct amount. For example, if the change is $3, we can receive it as three $1 coins, a $2 bill and a $1 coin, or in some other way. The combination of bills or coins used to give the change will depend on what the seller has available.

To delve deeper into the topic, I suggest the following resources:

1. How to calculate the change? - Article from Exame that provides a simple and straightforward explanation of how to calculate the change.

2. Change - Mathematics - Page of Just Mathematics with various activities and problems on calculating change in different situations.

3. Learn how to calculate change - Article from Portal Educação that teaches how to calculate change.

These resources are great starting points for learning about the topic and also for generating discussions and debates in the classroom.

Hands-on Activity

Activity Title: Playing with Change

Objective

The objective of this activity is to apply the concept of change in a real-world scenario through a simulated game, encouraging teamwork and enhancing students' calculation, communication, and problem-solving skills.

Description

Students will be divided into groups of 3 to 5 members. Each group will represent a store and students will take turns playing the role of seller and customer. They will simulate purchase and sale transactions and calculate the change that should be given. Additionally, they will need to record each transaction and their calculations.

Materials required

1. Toy "money" with different denominations of bills and coins.
2. Assorted items to represent the products sold in the store (can be drawings, real objects, etc.).
3. Price list for each item.
4. Notebook or sheet of paper for recording transactions.
5. Pens or pencils.

Step-by-step

1. Gather students in groups of 3 to 5 members. Explain the objective of the game, which is to simulate situations of buying and selling items, where it will be necessary to calculate the change.

2. Distribute the toy "money" and materials to each group.

3. Each group should organize their own "store", establishing which items are for sale and the price of each one.

4. After the organization, students should start the transactions. The student playing the role of the customer should choose a product, pay with a bill of a higher value and the student playing the role of the seller should calculate the change that should be returned.

5. Each transaction should be recorded, indicating the value of the product, the value paid and the change.

6. After one hour, students should switch roles.

7. All students should have the chance to be both the seller and the customer.

8. At the end of the activity, each group should review their notes and compare the calculated changes with the correct values.

Project Deliverables and Paper Writing

At the end of the project, each group should submit a detailed report of the activity, divided into:

1. Introduction: context of the theme "change", explaining its relevance in the real world and the objective of the project carried out.

2. Development: explain the theory behind the calculation of change, detail the activity carried out, indicate the methodology used and present the results obtained, inserting the notes of the transaction carried out.

3. Conclusions: return to the main points, express what was learned, and draw conclusions about the project. Here, students should also reflect on the importance of teamwork and the socio-emotional skills developed during the project.

4. Bibliography: list the sources used to learn about the topic and to elaborate both the project and the report.

This report should both demonstrate students' understanding of the concept of change and its practical application, and highlight the teamwork carried out.