Objectives (5 - 7 minutes)

1. Understanding the structure of a financial spreadsheet: The teacher should guide the students to understand the basic structure of a financial spreadsheet, highlighting the importance of each element (cells, rows, columns, formulas, etc.) and how they interact with each other.

2. Applying financial formulas in a spreadsheet: Students should be able to apply financial mathematical formulas in a spreadsheet, such as simple and compound interest, discount, etc. The teacher should ensure that students understand the meaning and purpose of each formula, as well as how to use them correctly.

3. Solving complex financial mathematics problems using spreadsheets: The ultimate goal is for students to be able to solve complex financial mathematics problems, such as calculating the future value of an investment, using spreadsheets. The teacher should provide practical examples and step-by-step guidance to help students achieve this skill.

   • Secondary Objectives:

     • Develop critical thinking and problem-solving skills: By solving financial mathematics problems, students will be able to develop their critical thinking and problem-solving skills, which are valuable skills in any field of study or career.

     • Enhance the ability to work with digital tools: The use of spreadsheets requires basic technology skills, such as typing, cell manipulation, etc. Therefore, this lesson will also serve to enhance students' digital skills.

Introduction (10 - 15 minutes)

1. Review of Previous Content: To start the lesson, the teacher should briefly review the financial mathematics concepts that were taught in previous classes. This includes simple and compound interest, discount, present and future value, among others. Additionally, it is important to remind students about the use of formulas in mathematics, as this will be essential for understanding the current topic.

2. Problem Situation: The teacher can present two problem situations to arouse students' interest and contextualize the topic. For example:

   • Situation 1: 'Imagine you are the manager of a clothing store and need to calculate the discount that should be applied to a product on sale. How would you do this quickly and efficiently?'

   • Situation 2: 'Suppose you are planning to invest your money in an investment fund that offers compound interest. How would you calculate the future value of your investment after a certain period of time?'

3. Contextualization: The teacher should highlight the importance of spreadsheets in real life, mentioning that they are widely used in companies, banks, financial institutions, etc. Additionally, one can talk about how spreadsheets can facilitate work and make it more efficient. For example, instead of manually calculating the interest on a loan, a spreadsheet can do this automatically.

4. Introduction to the Topic: To introduce the topic and capture students' attention, the teacher can share some curiosities or interesting stories about the use of spreadsheets:

   • Curiosity 1: Electronic spreadsheets, such as Microsoft Excel and Google Sheets, were invented in the 1970s, but only became widely used in the 1980s with the release of the first PC.

   • Curiosity 2: In 2013, a study found that 88% of spreadsheets contained errors, highlighting the importance of understanding how spreadsheets work and how to use them correctly.

5. Capturing Students' Attention: To arouse students' interest, the teacher can share examples of how spreadsheets are used in different fields, such as finance, engineering, sciences, etc. Additionally, one can talk about career possibilities for those with advanced spreadsheet skills, such as financial analyst, data scientist, etc.

Development (20 - 25 minutes)

1. Household Budget Spreadsheet Creation Activity (10 - 12 minutes): The teacher should divide the class into groups of 3 to 4 students and provide each group with a hypothetical scenario of a family that needs to organize their budget. Students should create a spreadsheet in Excel or Google Sheets to help the family track their expenses and income. The spreadsheet should include expense categories, such as food, housing, transportation, etc., and formulas to calculate the total expenses, total income, and balance.

   • Step 1: The teacher should explain the scenario and the spreadsheet requirements, clarifying any doubts students may have.

   • Step 2: Students, in their groups, should discuss and plan how they will organize the spreadsheet, deciding which expense categories to include and how to calculate the total expenses, total income, and balance.

   • Step 3: Students should create the spreadsheet, entering expense categories in the first column, income in the second column, and formulas to calculate the total expenses, total income, and balance in the appropriate cells.

   • Step 4: Once the spreadsheet is complete, students should analyze the results and discuss possible ways to save money or increase the family's income.

2. Compound Interest Calculation Activity (10 - 12 minutes): After the household budget spreadsheet creation activity, students should continue working in their groups. The teacher should provide each group with a new scenario: an investor who wants to calculate the future value of an investment with compound interest. Students should use the spreadsheet they created in the previous activity to solve the problem.

   • Step 1: The teacher should explain the scenario and the problem, clarifying any doubts students may have.

   • Step 2: Students, in their groups, should discuss and plan how to use the spreadsheet to calculate the future value of the investment. They should decide on the initial investment amount, the annual interest rate, and the time period.

   • Step 3: Students should use the compound interest formulas in the spreadsheet to calculate the future value of the investment.

   • Step 4: Once the calculation is completed, students should analyze the result and discuss what it means for the investor.

3. Group Discussion (3 - 5 minutes): After completing the activities, the teacher should promote a group discussion so that students can share their solutions and conclusions.

   • Step 1: The teacher should ask each group to briefly share how they created the household budget spreadsheet and how they solved the compound interest calculation problem.

   • Step 2: Students should listen attentively to the presentations of the other groups and ask questions if necessary.

4. Individual Reflection (2 - 3 minutes): To conclude the Development stage, the teacher should propose that students reflect individually on what they have learned. The teacher can ask guiding questions, such as:

   1. 'What was the most important concept you learned today?'

   2. 'What questions have not been answered yet?'

   3. 'How can you apply what you learned today in your life or in other subjects?'

   Students should write down their answers, which will be useful for reviewing the content in the Conclusion stage.

Return (8 - 10 minutes)

1. Group Review (3 - 4 minutes): The teacher should facilitate a group discussion to review each group's solutions and conclusions. Each group will have a maximum of 2 minutes to share their spreadsheets and the results of their calculations. During the presentations, the teacher should encourage other groups to ask questions and provide constructive feedback. The goal of this activity is to allow students to learn from each other and see different approaches to problem-solving.

   • Step 1: The teacher should ask each group to share their spreadsheets and explain the logic behind their formulas and calculations.

   • Step 2: Other groups should listen attentively and ask questions if necessary. They should also provide constructive feedback, highlighting what they found interesting or effective in the group's approach and suggesting possible improvements.

2. Connection to Theory (2 - 3 minutes): After the group presentations, the teacher should give a quick review of the theoretical concepts that were applied during the activities. The teacher should highlight how the financial mathematics formulas were used in creating the spreadsheets and in the calculations. Additionally, the teacher should reinforce the importance of understanding the theory behind the formulas so that students can apply them correctly in different contexts.

3. Reflection (2 - 3 minutes): To conclude the Return stage, the teacher should propose that students reflect on what they have learned. The teacher can ask guiding questions, such as:

   1. 'What was the most important concept you learned today?'

   2. 'What questions have not been answered yet?'

   3. 'How can you apply what you learned today in your life or in other subjects?'

   • Step 1: Students should think about the questions and write down their answers.

   • Step 2: After a minute of reflection, the teacher can invite some students to share their answers with the class. This can help start a discussion and clarify any remaining doubts or misunderstandings.

4. Teacher Feedback (1 minute): Finally, the teacher should provide feedback to students on their participation in the activities. The teacher should praise students' efforts, highlight strengths, and suggest areas for improvement. Additionally, the teacher should reinforce the importance of the topic and the skill of working with spreadsheets in real life, encouraging students to continue practicing and exploring the subject.

Conclusion (5 - 7 minutes)

1. Summary of Contents (2 - 3 minutes): The teacher should start the Conclusion stage by summarizing the main points covered during the lesson. This includes the structure of a financial spreadsheet, the application of financial formulas, and the resolution of complex financial mathematics problems using spreadsheets. The teacher should reinforce the most important concepts and clarify any remaining doubts.

   • Step 1: The teacher should summarize the main points of the lesson, reminding students about the importance of each concept and how they connect with each other.

   • Step 2: The teacher should use the review as an opportunity to clarify any misunderstandings or confusion that may still exist.

2. Connection between Theory, Practice, and Applications (1 - 2 minutes): The teacher should explain how the lesson connected the theory, practice, and applications of using spreadsheets in financial mathematics. This can be done by recalling the practical activities carried out during the lesson, the theoretical discussions that accompanied them, and the applications of using spreadsheets in real life.

   • Step 1: The teacher should highlight how the practical activities allowed students to apply and understand theoretical concepts in a real context.

   • Step 2: The teacher should emphasize the importance of spreadsheets in various areas of life, from managing household budgets to financial analysis in a company.

3. Extra Materials (1 minute): The teacher should suggest extra materials for students who want to deepen their knowledge of using spreadsheets in financial mathematics. These materials may include online videos, interactive tutorials, specialized websites, books, and articles. The teacher should encourage students to explore these resources on their own to reinforce what they learned in the classroom.

   • Step 1: The teacher should provide a list of recommended materials, along with brief descriptions of each and why they are useful.

   • Step 2: The teacher should explain how students can access these materials, whether through a school website, a library, or the internet.

4. Importance of the Topic (1 minute): To conclude, the teacher should reiterate the importance of using spreadsheets in financial mathematics. The teacher should emphasize that these skills are not only useful in an academic context, but also in daily life and in many careers. Additionally, the teacher should encourage students to continue practicing and exploring the use of spreadsheets, as this can open up many opportunities in the future.

   • Step 1: The teacher should emphasize how the skills learned in the lesson are valuable and relevant in the real world.

   • Step 2: The teacher should end the lesson with words of encouragement, encouraging students to continue learning and exploring the topic on their own.