Counting forward: Adding to a starting number by moving forward on a number line
- Start with the initial amount (5 apples)
- Count forward by the number being added (3 more)
- Keep track of each count
Sarah starts with 5 apples
5 → 6 → 7 → 8 (count 3 numbers forward)
Sarah has 8 apples total
Sarah has 8 apples now
• Addition: Combining two groups to find the total
• Counting forward: Moving ahead on the number line
• Visual representation: Using objects to understand the concept
Counting backward: Subtracting by moving backward on a number line
Tom starts with 9 cookies
9 → 8 → 7 → 6 → 5 (count 4 numbers backward)
Tom has 5 cookies left
Tom has 5 cookies left
• Subtraction: Taking away from a group to find what remains
• Counting backward: Moving behind on the number line
• Visual representation: Showing what is taken away
Grouping: Combining separate groups to find the total amount
Red balls = 4, Blue balls = 6
Count all balls together: 4 + 6 = 10
There are 10 balls in total
There are 10 balls in total
• Grouping: Separating items by characteristics (color)
• Addition: Combining groups to find the total
• Visual organization: Arranging items to make counting easier
Addition: Combining two or more groups to find the total
Subtraction: Taking away from a group to find what remains
Counting: Assigning numbers to objects in sequence
- Identify the problem: Understand what is being asked (total or remaining)
- Choose the operation: Addition for combining, subtraction for taking away
- Select the strategy: Count all, count on, or make ten
- Represent visually: Use objects, drawings, or number lines
- Calculate: Perform the counting process
- Verify: Check if the answer makes sense
• Count all: Count every item in both groups
• Count on: Start with the first number and count up
• Count back: Start with the first number and count down
• Make ten: Use combinations that add to 10
• Grouping: Organize items into groups for easier counting
Part-Part-Whole: Understanding how parts combine to make a whole
One More/One Less: Understanding consecutive numbers
Number Bonds: Pairs that combine to make a target number
- Look for doubles: 4 + 4 = 8, 5 + 5 = 10
- Use near doubles: 4 + 5 = (4 + 4) + 1 = 9
- Find tens partners: 7 + 3 = 10, 6 + 4 = 10
- Understand commutativity: 3 + 5 = 5 + 3
• Adding 0 doesn't change the number: 5 + 0 = 5
• Adding 1 gives the next number: 5 + 1 = 6
• Subtracting 0 doesn't change the number: 5 - 0 = 5
• Subtracting 1 gives the previous number: 5 - 1 = 4
• Order doesn't matter in addition: 3 + 4 = 4 + 3