Open Sentences Involving Addition and Subtraction of Numbers Mathematics Primary 2 Second Term Lesson Notes Week 8

Comprehensive Lesson Plan for Mathematics Primary 2 Second Term (Week 8)

Lesson Plan Overview

• Subject: Mathematics
• Class: Primary 2
• Term: Second Term
• Week: 8
• Age: 6–7 years
• Topic: Open Sentences Involving Addition and Subtraction of Numbers in Story Problems
• Sub-topic: Solving Story Problems Using Open Sentences
• Duration: 40 Minutes

Behavioural Objectives

At the end of the lesson, pupils should be able to:

1. Define and explain open sentences involving addition and subtraction.
2. Identify open sentences in story problems.
3. Solve story problems using open sentences with addition and subtraction.
4. Relate open sentences to real-life situations.

Keywords

• Open Sentence
• Addition
• Subtraction
• Story Problems

Set Induction

The teacher will begin by asking pupils real-life questions such as:

• “If you have 3 oranges and your friend gives you some more, how many will you have in total?”
• “If I have 10 pencils and give 4 to my friend, how many will I have left?”
  The teacher will use their responses to introduce the topic of solving open sentences in story problems.

Entry Behaviour

Pupils are already familiar with basic addition and subtraction operations from previous lessons.

Learning Resources and Materials

• Flashcards with story problems.
• Counters (e.g., bottle caps, sticks).
• Number charts.
• Pictures depicting addition and subtraction scenarios.

Building Background/Connection to Prior Knowledge

The teacher will remind pupils about previous lessons on addition and subtraction.

Embedded Core Skills

• Problem-solving
• Logical reasoning
• Communication and collaboration

Learning Materials

• Counters
• Flashcards
• Charts showing addition and subtraction problems

Reference Books

• Lagos State Scheme of Work for Primary 2 Mathematics
• Basic Mathematics for Primary Schools

Instructional Materials

• Flashcards
• Counters
• Picture cards

Content

Definition and Explanation

1. Open Sentences: These are mathematical statements with missing numbers that can be solved using addition or subtraction.
2. Story Problems: These are real-life situations presented in words, which require mathematical operations to solve.
3. Open sentences often look like this:
   • ___ + 5 = 10
   • 15 – ___ = 7
4. Solving open sentences involves finding the missing number that completes the equation.

Examples of Open Sentences in Story Problems

1. James has 7 apples. He gives some to his friend and has 4 left. How many apples did he give away?
   • Open Sentence: 7 – ___ = 4
   • Solution: 3 apples
2. A basket has ___ mangoes. If you add 6 mangoes, there are 12 in total. How many mangoes were in the basket initially?
   • Open Sentence: ___ + 6 = 12
   • Solution: 6 mangoes
3. Ada has 15 books. She lends 5 to her friend. How many books does she have left?
   • Open Sentence: 15 – ___ = 10
   • Solution: 10 books
4. A shopkeeper had ___ items. He sold 8 and was left with 12. How many items did he start with?
   • Open Sentence: ___ – 8 = 12
   • Solution: 20 items
5. David bought 5 sweets. He received some more from his friend, making a total of 11 sweets. How many sweets did his friend give him?
   • Open Sentence: 5 + ___ = 11
   • Solution: 6 sweets

Evaluation Questions

15 Fill-in-the-Blank Questions with Options

1. ___ + 6 = 12
   a) 5
   b) 6
   c) 7
   d) 4
2. 10 – ___ = 7
   a) 2
   b) 3
   c) 5
   d) 4
3. 20 – ___ = 15
   a) 4
   b) 5
   c) 6
   d) 8
4. ___ + 8 = 15
   a) 6
   b) 7
   c) 5
   d) 8
5. 12 – ___ = 6
   a) 4
   b) 5
   c) 6
   d) 7

(Continue with similar questions up to 15)

Class Activity Discussion: 15 FAQs with Answers

1. What is an open sentence?
   • An open sentence is a mathematical problem with a missing number.
2. How do you solve an open sentence?
   • By finding the missing number.
3. Give an example of an open sentence involving addition.
   • ___ + 5 = 10.

(Continue with similar FAQs up to 15)

Presentation Structure

1. Step 1: Revise the previous topic on addition and subtraction.
2. Step 2: Introduce the new topic and explain open sentences using simple examples.
3. Step 3: Engage pupils in solving examples together.
4. Step 4: Encourage pupils to create their own story problems and solve.

Teacher’s Activities

• Explain open sentences with practical examples.
• Demonstrate solving open sentences using counters.
• Guide pupils in solving examples on the board.
• Divide pupils into groups for collaborative problem-solving.

Learners’ Activities

• Listen and respond to teacher’s explanations.
• Solve open sentences in groups and individually.
• Share their story problems with the class.

Assessment: 10 Short-Answer Questions

1. Solve: ___ + 7 = 10.
2. 15 – ___ = 8.
3. Write a story problem for 12 – ___ = 5.
4. Solve: ___ + 4 = 9.
5. How do you solve 20 – ___ = 15?

(Continue up to 10 questions)

Conclusion

The teacher reviews pupils’ answers, marks their work, and provides corrections. Pupils summarize what they learned in the lesson.

SEO Elements

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• Meta Description: Learn how to solve open sentences involving addition and subtraction in story problems for Primary 2 pupils. Simplified and engaging lesson plan.

Fill-in-the-Blank Questions with Options (a, b, c, or d)

1. ___ + 6 = 12
   a) 4
   b) 5
   c) 6
   d) 7
   Answer: d) 6
2. 10 – ___ = 4
   a) 2
   b) 4
   c) 6
   d) 5
   Answer: c) 6
3. ___ + 8 = 15
   a) 5
   b) 6
   c) 7
   d) 8
   Answer: c) 7
4. 20 – ___ = 15
   a) 5
   b) 6
   c) 4
   d) 7
   Answer: a) 5
5. ___ + 5 = 10
   a) 5
   b) 6
   c) 4
   d) 3
   Answer: a) 5
6. 14 – ___ = 9
   a) 3
   b) 4
   c) 5
   d) 6
   Answer: c) 5
7. ___ + 3 = 7
   a) 2
   b) 3
   c) 4
   d) 5
   Answer: c) 4
8. 12 – ___ = 6
   a) 6
   b) 5
   c) 7
   d) 8
   Answer: a) 6
9. ___ + 4 = 10
   a) 6
   b) 5
   c) 4
   d) 7
   Answer: a) 6
10. 9 – ___ = 3
    a) 4
    b) 5
    c) 6
    d) 7
    Answer: c) 6
11. ___ + 9 = 16
    a) 7
    b) 8
    c) 6
    d) 5
    Answer: a) 7
12. 18 – ___ = 10
    a) 6
    b) 7
    c) 8
    d) 9
    Answer: d) 8
13. ___ + 2 = 5
    a) 3
    b) 4
    c) 2
    d) 1
    Answer: a) 3
14. 15 – ___ = 7
    a) 7
    b) 8
    c) 6
    d) 5
    Answer: b) 8
15. ___ + 10 = 20
    a) 5
    b) 10
    c) 8
    d) 6
    Answer: b) 10

Frequently Asked Questions (FAQs) with Answers

1. What is an open sentence?
   • An open sentence is a math problem with a missing number to solve.
2. How do you identify an open sentence?
   • An open sentence has a blank space or a missing number in the equation.
3. What is the purpose of solving open sentences?
   • To find the missing number that makes the equation true.
4. What operations can be used in open sentences?
   • Addition, subtraction, multiplication, or division.
5. What is a story problem?
   • A real-life situation described in words that requires solving a math problem.
6. What is an example of an open sentence with addition?
   • ___ + 4 = 9.
7. What is an example of an open sentence with subtraction?
   • 12 – ___ = 8.
8. Why are story problems important?
   • They help pupils apply math skills in real-life situations.
9. How can you solve an open sentence?
   • By using the opposite operation to find the missing number.
10. What tools can help solve open sentences?
    • Counters, number lines, or mental math.
11. What should you do first in a story problem?
    • Understand the problem and identify the numbers involved.
12. Can open sentences involve only whole numbers?
    • Yes, for Primary 2, they involve whole numbers.
13. How do open sentences relate to daily life?
    • They help solve real-life problems like counting items or finding change.
14. What is the answer to ___ + 6 = 10?
    • The missing number is 4.
15. How do you create a story problem from ___ + 5 = 9?
    • “John has 5 apples. His friend gives him some more, and now he has 9 apples. How many did his friend give him?”

Evaluation Questions

1. Solve: ___ + 5 = 8.
2. Solve: 15 – ___ = 10.
3. Write a story problem for ___ + 6 = 12.
4. Solve: 20 – ___ = 13.
5. Solve: ___ + 4 = 9.
6. How do you find the missing number in 10 – ___ = 4?
7. Write a story problem for 14 – ___ = 7.
8. Solve: ___ + 10 = 15.
9. What number is missing in ___ + 3 = 8?
10. Solve: 12 – ___ = 5.