Lesson Plan | Active Learning | Addition and Subtraction of Natural Numbers Less than 100

Assumptions: This Active Lesson Plan assumes: a 100-minute class, prior student study with both the Book and the start of Project development, and that only one activity (among the three suggested) will be chosen to be conducted during the class, as each activity is designed to take up a significant portion of the available time.

Objectives

Duration: (5 - 10 minutes)

The objectives stage is crucial to guide the focus of students and the teacher towards the specific learning goals of the lesson. By clearly establishing what is expected to be achieved, both students and the teacher can better prepare for classroom activities, ensuring that class time is used effectively and purposefully. These objectives also serve to align expectations and provide a clear criterion for assessing progress throughout the lesson.

Main Objectives:

1. Develop students' ability to add and subtract two-digit numbers, using or not specific algorithms to facilitate calculations.

2. Enhance problem-solving skills involving the addition and subtraction of numbers up to two digits, promoting the practical application of these operations.

Side Objectives:

1. Encourage the development of analytical skills and logical reasoning in students through practical and interactive activities.
2. Encourage collaboration and communication among students during group activities, fostering a cooperative learning environment.

Introduction

Duration: (15 - 20 minutes)

The introduction aims to engage students with the theme of the lesson through problem situations that utilize previously acquired knowledge. By presenting problems they might encounter in their daily lives, the contextualization helps recognize the relevance of what they are learning, increasing interest and motivation to explore the topic further.

Problem-Based Situations

1. Imagine you are in a candy store and want to buy 47 gummy bears and 32 chocolates. How many items will you take home in total?

2. If you have 85 stickers and decide to give 29 to your best friend, how many stickers will you have left?

Contextualization

Addition and subtraction are fundamental skills that we use in our daily lives, from calculating change during a purchase to equally distributing snacks at a party. Knowing how to manipulate numbers helps not only in daily tasks but also develops logical reasoning and the ability to solve more complex problems.

Development

Duration: (75 - 80 minutes)

The development stage is designed to apply the concepts of addition and subtraction in a practical and engaging manner, utilizing methods that stimulate active participation from students. The proposed activities are designed to involve students in scenarios that replicate real or playful situations, helping them consolidate their learning in a fun and meaningful way. Each activity is planned to be self-contained, ensuring that regardless of the teacher's choice, the learning objectives are achieved.

Activity Suggestions

It is recommended to carry out only one of the suggested activities

Activity 1 - Numbers Supermarket

> Duration: (60 - 70 minutes)

- Objective: Practice addition and subtraction in a practical and fun context, encouraging teamwork and quick reasoning.

- Description: In this activity, students are divided into groups, and each group is tasked with 'buying' items for a birthday party using a price list and a fixed amount of imaginary money. Each item has a price, and students must add and subtract values to stay within the budget.

- Instructions:

• Divide the class into groups of up to 5 students.

• Distribute the price list of party items and the amount of imaginary money.

• Students should choose the items they wish to 'buy', adding their prices to not exceed the available amount.

• For each chosen item, a group member must explain the addition or subtraction made to reach the total spent so far.

• At the end, each group presents what they managed to 'buy' and how they allocated the money.

Activity 2 - Balloon Race

> Duration: (60 - 70 minutes)

- Objective: Develop addition and subtraction skills in a dynamic and competitive environment, also promoting cooperation and communication among students.

- Description: Students participate in a relay race where each stage involves solving addition or subtraction problems to advance. Each correct answer allows the group to move on to the next station, where a new challenge awaits.

- Instructions:

• Organize the room into stations, each with an addition or subtraction problem.

• Divide the students into groups and align each group to their starting station.

• At the signal, the first student from each group solves the problem at their station, and if correct, advances to the next station.

• The next group member solves the new problem and so on, until the group completes the circuit.

• The group that finishes first, solving all problems correctly, wins.

Activity 3 - Mathematical Mystery

> Duration: (60 - 70 minutes)

- Objective: Stimulate critical thinking and the application of addition and subtraction in a playful context, encouraging collaboration and logical reasoning.

- Description: In this activity, students use their addition and subtraction skills to solve a 'mystery' in which they must discover combinations of numbers that fit given clues. Each clue leads to another until the group solves the final riddle.

- Instructions:

• Distribute a set of clues to each group, where each clue involves an addition or subtraction operation.

• Students must solve the operations and note the results to discover the next clue.

• Each solved clue leads to another, forming a chain until the final riddle.

• The first group to solve the final mystery wins a small prize.

Feedback

Duration: (10 - 15 minutes)

This stage of the lesson plan is essential to consolidate students' learning, allowing them to reflect on the learning process and share their experiences. The group discussion helps reinforce mathematical concepts by allowing students to express their own understandings and hear the perspectives of their peers, promoting deeper and more collaborative learning.

Group Discussion

Promote a group discussion with all students, where the groups share what they learned while conducting the experience and their conclusions. Suggest starting the discussion with the following approach: 'Let's share what each group discovered during the activities. I would like each group to mention an interesting or challenging point they encountered and how they overcame it.'

Key Questions

1. What strategies did your group use to solve addition and subtraction problems more quickly?

2. How did you help each other in the group activities?

3. Was there any mistake your group made initially, and how did you correct it?

Conclusion

Duration: (5 - 10 minutes)

The conclusion stage is crucial to solidify students' understanding of the topic worked on. By summarizing key points, connecting theory to practice, and highlighting relevance to daily life, this section helps students internalize learning and see the practical value of the mathematical skills developed. Moreover, it sets the stage for future lessons, reinforcing the importance of applying mathematical knowledge in various situations.

Summary

In the conclusion of the lesson, a summary is made emphasizing the procedures of addition and subtraction of natural numbers less than 100, reiterating the strategies and algorithms used. It recaps the importance of accuracy in calculations and how the acquired skills apply to various practical situations.

Theory Connection

During the lesson, the theoretical concepts of addition and subtraction were applied in practical activities such as 'Numbers Supermarket', which simulated a shopping experience, and 'Balloon Race', which incorporated movement and competition into learning. This demonstrated how mathematics is intrinsically linked to everyday life, facilitating students' understanding and retention of knowledge.

Closing

At the end, the relevance of learning addition and subtraction for students' daily lives was highlighted, from calculating change to managing small amounts of money. These skills are essential not only for academic success in mathematics but also for everyday life, helping students become more independent and confident in their mathematical abilities.