➖ Understanding Subtraction - First Grade

What is Subtraction? Subtraction means "taking away" or finding out "how many are left."

Minuend - Subtrahend = Difference

Minuend: The number you start with (bigger number)
Subtrahend: The number you take away
Difference: The answer (what's left)

Example: 8 - 3 = 5

8 (Minuend) - 3 (Subtrahend) = 5 (Difference)

In words: You have 8 apples. You eat 3 apples. You have 5 apples left.

🎨 1. Subtract with Pictures - Numbers Up to 10

Strategy: Cross out objects to show subtraction!

Example 1: 5 - 2 = ?

🍎 🍎 🍎 🍎 🍎 (Start with 5 apples)
❌ ❌ 🍎 🍎 🍎 (Cross out 2)

5 - 2 = 3

Answer: 3 apples are left

Example 2: 7 - 4 = ?

⭐ ⭐ ⭐ ⭐ ⭐ ⭐ ⭐ (Start with 7 stars)
❌ ❌ ❌ ❌ ⭐ ⭐ ⭐ (Cross out 4)

7 - 4 = 3

Answer: 3 stars are left

Example 3: 9 - 5 = ?

🍊 🍊 🍊 🍊 🍊 🍊 🍊 🍊 🍊 (Start with 9 oranges)
❌ ❌ ❌ ❌ ❌ 🍊 🍊 🍊 🍊 (Cross out 5)

9 - 5 = 4

Answer: 4 oranges are left

Example 4: 10 - 6 = ?

🎈 🎈 🎈 🎈 🎈 🎈 🎈 🎈 🎈 🎈 (Start with 10 balloons)
❌ ❌ ❌ ❌ ❌ ❌ 🎈 🎈 🎈 🎈 (Cross out 6)

10 - 6 = 4

Answer: 4 balloons are left

Steps to Subtract with Pictures:

Draw or count the total number of objects (minuend)
Cross out the number you need to subtract (subtrahend)
Count how many objects are NOT crossed out
That's your answer (difference)!

✏️ 2. Subtraction Sentences - Numbers Up to 10

Subtraction Sentence: A complete math statement with numbers and symbols!

Number - Number = Answer

The minus sign (-) means "subtract" or "take away"

All Subtraction Facts (0-10):

Subtracting from 1:
1 - 0 = 1 | 1 - 1 = 0

Subtracting from 2:
2 - 0 = 2 | 2 - 1 = 1 | 2 - 2 = 0

Subtracting from 3:
3 - 0 = 3 | 3 - 1 = 2 | 3 - 2 = 1 | 3 - 3 = 0

Subtracting from 4:
4 - 0 = 4 | 4 - 1 = 3 | 4 - 2 = 2 | 4 - 3 = 1 | 4 - 4 = 0

Subtracting from 5:
5 - 0 = 5 | 5 - 1 = 4 | 5 - 2 = 3 | 5 - 3 = 2 | 5 - 4 = 1 | 5 - 5 = 0

Subtracting from 6:
6 - 0 = 6 | 6 - 1 = 5 | 6 - 2 = 4 | 6 - 3 = 3 | 6 - 4 = 2 | 6 - 5 = 1 | 6 - 6 = 0

Subtracting from 7:
7 - 0 = 7 | 7 - 1 = 6 | 7 - 2 = 5 | 7 - 3 = 4 | 7 - 4 = 3 | 7 - 5 = 2 | 7 - 6 = 1 | 7 - 7 = 0

Subtracting from 8:
8 - 0 = 8 | 8 - 1 = 7 | 8 - 2 = 6 | 8 - 3 = 5 | 8 - 4 = 4 | 8 - 5 = 3 | 8 - 6 = 2 | 8 - 7 = 1 | 8 - 8 = 0

Subtracting from 9:
9 - 0 = 9 | 9 - 1 = 8 | 9 - 2 = 7 | 9 - 3 = 6 | 9 - 4 = 5 | 9 - 5 = 4 | 9 - 6 = 3 | 9 - 7 = 2 | 9 - 8 = 1 | 9 - 9 = 0

Subtracting from 10:
10 - 0 = 10 | 10 - 1 = 9 | 10 - 2 = 8 | 10 - 3 = 7 | 10 - 4 = 6 | 10 - 5 = 5
10 - 6 = 4 | 10 - 7 = 3 | 10 - 8 = 2 | 10 - 9 = 1 | 10 - 10 = 0

💡 Practice Tips:

Learn subtraction facts by heart through daily practice
Use flashcards to memorize basic facts
Practice counting backwards to help with subtraction
Remember: subtraction is the opposite of addition!

Complete the Subtraction Sentence

Find the Missing Number:

7 - ? = 4 → Think: What number makes this true?
Answer: 7 - 3 = 4

? - 5 = 2 → Think: What number minus 5 equals 2?
Answer: 7 - 5 = 2

9 - 6 = ? → Think: 9 minus 6 equals what?
Answer: 9 - 6 = 3

➡️ 3. Subtraction Using Number Lines - Numbers Up to 10

Number Line Strategy: Start at the first number and jump BACKWARDS!

Start at the Minuend → Count backwards by the Subtrahend

Number Line 0 to 10:

0 - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10

Example 1: 8 - 3 = ?

Step 1: Start at 8 on the number line

Step 2: Count backwards 3 times (jump left 3 times)

Step 3: 8 → 7 → 6 → 5 (You land on 5!)

8 - 3 = 5

0 - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10
⬆ Start here ⬅ Jump 3 left

Example 2: 10 - 4 = ?

Step 1: Start at 10

Step 2: Jump backwards 4 times

Step 3: 10 → 9 → 8 → 7 → 6

10 - 4 = 6

Example 3: 7 - 5 = ?

Step 1: Start at 7

Step 2: Jump backwards 5 times

Step 3: 7 → 6 → 5 → 4 → 3 → 2

7 - 5 = 2

Example 4: 9 - 7 = ?

Step 1: Start at 9

Step 2: Jump backwards 7 times

Step 3: 9 → 8 → 7 → 6 → 5 → 4 → 3 → 2

9 - 7 = 2

How to Use a Number Line:

Find the starting number (minuend) on the number line
Count backwards (move LEFT) the number of times shown by the subtrahend
The number where you land is your answer!
Remember: Subtraction moves LEFT on the number line

🔢 4. Subtract Zero and All

Special Rule 1: Subtracting Zero

Zero Rule: When you subtract zero, nothing changes!

n - 0 = n

Any number minus zero equals that same number!

Subtract Zero Examples:

0 - 0 = 0
1 - 0 = 1
2 - 0 = 2
3 - 0 = 3
4 - 0 = 4
5 - 0 = 5
6 - 0 = 6
7 - 0 = 7
8 - 0 = 8
9 - 0 = 9
10 - 0 = 10

Think About It:

🍎 🍎 🍎 🍎 🍎 (You have 5 apples)
You take away 0 apples
🍎 🍎 🍎 🍎 🍎 (You still have 5 apples!)

5 - 0 = 5

💡 Memory Trick: When you subtract zero, you're not taking anything away, so the number stays the same!

Special Rule 2: Subtract All (Subtract a Number from Itself)

Subtract All Rule: When you subtract a number from itself, you always get zero!

n - n = 0

Any number minus itself equals zero!

Subtract All Examples:

0 - 0 = 0
1 - 1 = 0
2 - 2 = 0
3 - 3 = 0
4 - 4 = 0
5 - 5 = 0
6 - 6 = 0
7 - 7 = 0
8 - 8 = 0
9 - 9 = 0
10 - 10 = 0

Think About It:

🎈 🎈 🎈 🎈 (You have 4 balloons)
❌ ❌ ❌ ❌ (You take away all 4 balloons)
(You have 0 balloons left!)

4 - 4 = 0

💡 Memory Trick: If you take away everything you have, you have nothing left (zero)!

Special Rule 3: Subtracting from Zero

Important Note: You cannot subtract a positive number from zero (in first grade)!

0 - 0 = 0 ✓

This is the only subtraction from zero we learn in first grade!

Why? You can't take away something when you have nothing to start with!

If you have 0 apples, you can't take away 3 apples. That doesn't make sense!

📊 Subtraction Vocabulary Chart

Important Words to Know:

Subtract: To take away or remove
Minus (-): The subtraction symbol
Difference: The answer in subtraction
Minuend: The starting number (bigger number)
Subtrahend: The number being taken away
Equals (=): Shows the answer
Take Away: Another way to say subtract
How Many Left?: A question asking for subtraction