Basic Subtraction (Up To 10) Study Notes

Subtraction is a fundamental math skill that helps us understand how to take things away or find out how many are left. For kindergarteners, we focus on subtracting numbers up to 10, meaning our starting number will never be more than 10, and our answer will also be within that range.

What is Subtraction? ➖

Subtraction means taking away a part from a whole to find out how much is left. It tells us the difference between two numbers.

• The minus sign is \( - \). It tells us to take away.
• The equals sign is \( = \). It tells us the answer.

For example, if you have 5 apples and you eat 2, you want to know how many apples are left. That's subtraction!

\[ 5 - 2 = 3 \]

This means 5 take away 2 equals 3. So, 3 apples are left.

Key Words for Subtraction 🔑

When you hear these words, it's often a clue that you need to subtract:

• Take away
• Minus
• Left or How many are left?
• Difference
• Fewer

How to Subtract (Strategies Up To 10) 🤔

There are many fun ways to subtract numbers! Here are some simple strategies:

1. Using Pictures 🖼️

This is a great way to visualize taking away.

1. Draw the first number as objects (like circles or stars).
2. Cross out the number you are taking away.
3. Count how many objects are left.

Example: \( 7 - 3 = \text{?} \)

Imagine 7 circles: ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫

Now, cross out 3 circles: ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ ⚫

Count the circles left: There are 4 circles left.

\[ 7 - 3 = 4 \]

2. Using Your Fingers 🖐️

Your fingers are always with you and are perfect for subtracting small numbers!

1. Hold up the number of fingers you start with.
2. Fold down the number of fingers you are taking away.
3. Count the fingers that are still standing up.

Example: \( 6 - 2 = \text{?} \)

Hold up 6 fingers. Fold down 2 fingers. How many are left? 4 fingers.

\[ 6 - 2 = 4 \]

3. Using a Number Line 📏

A number line helps you jump backward to find the answer.

1. Find the first number on the number line.
2. Hop backward (to the left) the number of steps you are taking away.
3. The number you land on is your answer.

Example: \( 9 - 4 = \text{?} \)

Start at 9. Hop back 4 times:

• 1st hop: to 8
• 2nd hop: to 7
• 3rd hop: to 6
• 4th hop: to 5

You land on 5.

\[ 9 - 4 = 5 \]

Understanding Zero in Subtraction 0️⃣

Zero is a special number in subtraction!

• Subtracting Zero: When you take away zero, you take away nothing. So, the number stays the same.

  Example: \( 5 - 0 = 5 \)

  If you have 5 cookies and eat 0, you still have 5 cookies.

• Subtracting a Number from Itself: When you take away a number from the exact same number, you are left with nothing.

  Example: \( 4 - 4 = 0 \)

  If you have 4 toys and give away all 4, you have 0 toys left.

Practice Basic Subtraction Facts (Up To 10) ✅

Here's a table with some common subtraction facts you can practice:

Problem	Answer
\( 3 - 1 \)	\( 2 \)
\( 5 - 3 \)	\( 2 \)
\( 8 - 2 \)	\( 6 \)
\( 10 - 5 \)	\( 5 \)
\( 7 - 4 \)	\( 3 \)
\( 9 - 1 \)	\( 8 \)
\( 6 - 6 \)	\( 0 \)
\( 4 - 0 \)	\( 4 \)

Keep practicing these to become a subtraction expert!