Subject: Mathematics (Numeracy) | Class: Primary 1 | Term: 3rd Term | Week: 3
Previous Lesson: Addition of Numbers — Week 2
Learning Objectives
- Identify and read correctly the numbers 1–190.
- Write correctly the numbers 1–190.
- Count in 2s, 3s, 5s and 10s.
- Identify mathematical signs (+, −, =).
- Add and subtract two whole numbers with sum not more than 50.
Lesson 1 — Mathematical Signs
The + Sign (Plus / Addition)
The + sign means plus, addition, sum or put together. We place it between two numbers to show that the second number is added to the first. Example: 1 + 2, 7 + 5, 8 + 4.
The − Sign (Minus / Subtraction)
The − sign means minus, subtraction, take away or difference. We place it between two numbers to show that the second is taken away from the first. Example: 2 − 1, 4 − 2, 11 − 6.
The = Sign (Equal To)
The = sign means equal to. We place it after addition or subtraction to show the result. Example: 5 + 1 = 6, 7 − 5 = 2.
Work Exercise
1. Put an addition sign between the numbers: 5 and 3 | 7 and 4 | 2 and 3 | 6 and 6
2. Put a subtraction sign between the numbers: 5 and 3 | 4 and 1 | 10 and 5 | 7 and 0
3. Add or subtract using = sign: 5 + 1 = ___ | 1 + 2 = ___ | 7 − 5 = ___ | 4 − 2 = ___
Lesson 2 — Skip Counting in 2s and 3s
Skip Count in 2s
2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50
Add in 2s: 2 → 2+2=4 → 4+2=6 → 6+2=8 → 8+2=10 → … → 18+2=20 (up to 50)
Skip Count in 3s
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48
Add in 3s: 3 → 3+3=6 → 6+3=9 → 9+3=12 → 12+3=15 → … → 27+3=30 (up to 50)
Lesson 3 — Skip Counting in 5s and 10s
Skip Count in 5s
5, 10, 15, 20, 25, 30, 35, 40, 45, 50
Add in 5s: 5 → 5+5=10 → 10+5=15 → 15+5=20 → 20+5=25 → 25+5=30 → 30+5=35 → 35+5=40 → 40+5=45 → 45+5=50
Skip Count in 10s
10, 20, 30, 40, 50, 60, 70, 80, 90, 100
Add in 10s: 10 → 10+10=20 → 20+10=30 → 30+10=40 → 40+10=50
Lesson 4 — Addition of Whole Numbers (Not more than 50)
Examples: 10 + 5 = 15 | 11 + 7 = 18 | 30 + 5 = 35 | 10 + 10 = 20
Working Exercise
Add the following: 11 and 15 | 15 and 6 | 23 and 17 | 17 and 17
Lesson 5 — Subtraction of Whole Numbers (Not more than 50)
Examples: 26 − 15 = 11 | 15 − 10 = 5 | 27 − 11 = 16 | 45 − 30 = 15 | 10 − 10 = 0
Working Exercise
Subtract the following: 23 and 13 | 15 and 16 | 23 and 17 | 17 and 17
Lesson Evaluation
- Identify and read correctly the numbers 1–190.
- Write correctly the numbers 1–190.
- Count in 2s, 3s, 5s and 10s.
- Identify mathematical signs +, − and =.
- Add and subtract two whole numbers with sum not more than 50.
Next Lesson: Money — Nigerian Currencies — Week 4