Counting On: Start with the larger number and count forward
- Start with the larger number (5)
- Count on the smaller number (3 more)
- 5, 6, 7, 8
Start with 5 because it's larger than 3
Count 3 more: 6, 7, 8
5 + 3 = 8
5 + 3 = 8
• Counting On: Start with the larger addend
• Sequential Counting: Count forward by the amount of the smaller number
• Number Recognition: Understand that numbers represent quantities
Counting Back: Start with the first number and count backward
Begin with 8
Count back 3: 7, 6, 5
8 - 3 = 5
8 - 3 = 5
• Counting Back: Start with the minuend (first number)
• Sequential Counting: Count backward by the subtrahend (second number)
• Subtraction Concept: Removing a quantity from another quantity
Number Line: Visual representation showing numbers in order
Place finger on 4
Move 2 spaces to the right: 5, 6
We land on 6
4 + 2 = 6
• Number Line Direction: Right for addition, left for subtraction
• Sequential Movement: Move one space for each unit
• Position Recognition: Identify where you land after movement
- • Counting On: Start with the larger number
- • Doubles: Adding the same number (5+5)
- • Near Doubles: One number is one more than the other (5+6)
- • Making Ten: Break apart numbers to make 10 (8+5 = 8+2+3)
- • Counting Back: Start with the first number
- • Think Addition: Use known addition facts (8-3: think 3+?=8)
- • Part-Part-Whole: Understanding that subtraction finds a missing part
Addition: Combining two or more quantities
Subtraction: Taking away or finding the difference
Strategy: A plan to solve a math problem
- Read the problem: Understand what's being asked
- Choose a strategy: Counting on, counting back, number line
- Apply the strategy: Follow the steps of your chosen method
- Check your answer: Does it make sense?
7 + 2 = ?
4 + 5 = ?
3 + 6 = ?
8 + 1 = ?
9 - 3 = ?
7 - 2 = ?
8 - 4 = ?
6 - 1 = ?
- • Read the problem slowly
- • Identify if it's addition (+) or subtraction (-)
- • Choose the best strategy for you
- • Check your answer by counting again
• In addition, the answer is called the sum
• In subtraction, the answer is called the difference
• The number being added to is called the addend
• The number being subtracted is called the subtrahend
Questions & Answers
Question: I get confused when doing 4 + 5. Should I count on from 4 or from 5? How do I know which number is bigger?
Answer: Great question! When using the counting on strategy, always start with the larger number. In 4 + 5, the larger number is 5, so you would start counting from 5.
To identify which number is larger, you can:
- Think about which number comes later when counting: 1, 2, 3, 4, 5 - since 5 comes after 4, it's larger
- Use your fingers - hold up 5 fingers and 4 fingers to compare
- Draw dots - draw 5 dots and 4 dots to see which group has more
So for 4 + 5, you would count: 5, 6, 7, 8, 9. The answer is 9!
Starting with the larger number means fewer counts, which is faster and less likely to cause mistakes.
Question: When I do 7 - 3, I sometimes forget whether to count forward or backward. How can I remember?
Answer: Here's a helpful way to remember:
- Subtraction means taking away - when you take something away, you have less
- Think of it like eating cookies: if you have 7 cookies and eat 3, you end up with fewer cookies
- On a number line, subtraction moves you backward (to the left) toward smaller numbers
So for 7 - 3, you start at 7 and count backward: 6, 5, 4. You end up with 4!
Another trick: subtraction is the opposite of addition, just like going backward is the opposite of going forward.
Question: My child seems to struggle with understanding when to add versus subtract in word problems. Any suggestions?
Answer: This is very common! Here are strategies to help identify operations in word problems:
- Look for key words: Words like "more," "altogether," "total," "combined" often mean addition. Words like "less," "left," "take away," "difference" often mean subtraction.
- Act out the problem: Use physical objects to demonstrate what's happening in the story.
- Draw a picture: Visualizing helps children see if things are coming together or going apart.
- Ask: "Are we putting together or taking away?"
Example: "Sara had 5 apples. She got 3 more." → Getting more means combining → Addition
"Tom had 8 cookies. He ate 3." → Eating takes away → Subtraction