Counting Worksheets for Kindergarten 1-20 - Addition & Subtraction Strategies

Master counting skills from 1 to 20 with visual exercises, step-by-step solutions, and interactive learning activities for kindergarteners transitioning to first grade.

Counting Concepts & Visuals (1-20)
1-20 = 🐻🐻🐻... = 20
Numbers 1 to 20
🐻
🐼
🐨
🐯
🦁
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Forward Counting
1→2→3→...→20
Adding one more
Backward Counting
20→19→18→...→1
Taking one away
Skip Counting
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
Counting by 2s
Counting Rule: Each object gets one number in order
Number Recognition: Know each number symbol and name
Quantity Understanding: Connect number to amount of objects
Counting Exercises Solutions (1-20)
1 Counting Addition (1-20)
Exercise 1
Count the bears:
8
+
5
=
?
8 + 5 = ?
Definition:

Addition: Combining groups to find total amount

Counting Method:
  1. Count first group: 1, 2, 3, 4, 5, 6, 7, 8
  2. Continue counting: 9, 10, 11, 12, 13
  3. Total count is the answer
Step 1: Count first group

Red bears: 1, 2, 3, 4, 5, 6, 7, 8

Step 2: Count second group

Blue bears: 9, 10, 11, 12, 13

Step 3: Find total

All bears: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13

8 + 5 = 13
Final answer:

There are 13 bears in total

Applied rules:

• Counting forward: Start from first number and continue

• Combining: Total includes all objects

• Sequential counting: One number per object

2 Counting Subtraction (1-20)
Exercise 2
Count the pandas:
15
-
6
=
?
15 - 6 = ?
Definition:

Subtraction: Taking away to find remaining amount

Step 1: Count total objects

All pandas: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15

Step 2: Take away objects

Remove 6 pandas: 14, 13, 12, 11, 10, 9

Step 3: Count remaining

Remaining pandas: 1, 2, 3, 4, 5, 6, 7, 8, 9

15 - 6 = 9
Final answer:

There are 9 pandas left

Applied rules:

• Counting backward: Start from total and remove

• Removing: Subtract means take away

• Remaining count: What's left after removal

3 Skip Counting (1-20)
Exercise 3
Count by 5s:
5, 10, ?, 20
Definition:

Skip Counting: Counting by equal intervals

Step 1: Identify pattern

Each number increases by 5

Step 2: Continue pattern

After 10 comes 10 + 5 = 15

Step 3: Verify sequence

5, 10, 15, 20 ✓

Missing number: 15
Final answer:

The missing number is 15

Applied rules:

• Pattern recognition: Find the interval

• Consistent addition: Same number added each time

• Sequence completion: Continue the pattern

Counting Strategies & Tips (1-20)
Counting 1-20 + Strategy = Success!
Smart Counting Up to 20
Key definitions:

Counting: Assigning numbers to objects in order

Addition: Combining groups to find total

Subtraction: Removing part to find remainder

Place Value: Understanding tens and ones in numbers 10-20

Counting methodology:
  1. Point and count: Touch each object once
  2. Keep track: Remember last number counted
  3. Combine or separate: Use addition/subtraction
  4. Check answer: Count again to verify
  5. Group by tens: For numbers over 10, group into tens and ones
Tip 1: Use fingers to help count when starting out (up to 20).
Tip 2: Draw circles around objects to keep track.
Tip 3: Say numbers aloud as you count.
Tip 4: Use objects like blocks or toys to practice.
Tip 5: Group objects into tens to understand place value.
Common mistakes: Double-counting, skipping numbers, losing place.
Practice tips: Count daily objects, play counting games, use songs.
Transition tip: Focus on numbers 11-20 as they are often challenging.
Counting rules to remember:

• One-to-one correspondence: Each object gets one number

• Order irrelevance: Order of counting doesn't matter

• Cardinality: Last number counted is the total

• Spatial arrangement: Objects can be rearranged

• Place value: Numbers 11-20 have one ten and some ones

Complete Summary: Counting Worksheets for Kindergarten 1-20

Definitions of Key Concepts

Counting: The process of determining the total number of objects in a set by assigning numbers to them in sequential order from 1 to 20.

Addition: A mathematical operation that combines two or more quantities to find their total sum.

Subtraction: A mathematical operation that finds the difference between two quantities by removing one from another.

One-to-One Correspondence: The principle that each object in a set is assigned exactly one number word during counting.

Cardinality: The concept that the last number counted represents the total quantity in the set.

Place Value: Understanding that numbers 11-20 consist of one ten and some ones (e.g., 15 = 10 + 5).

Skip Counting: Counting by equal intervals (such as 2s, 5s, or 10s) instead of counting by ones.

Core Rules and Principles

Stable Order Rule: Number words must be recited in the same sequence every time.

Order Irrelevance Principle: The total count remains the same regardless of the order in which objects are counted.

Abstraction Principle: Any collection of objects can be counted, whether tangible or abstract.

Addition Rule: Adding more objects to a set increases the total count.

Subtraction Rule: Removing objects from a set decreases the total count.

Conservation of Number: The total quantity remains the same even when objects are rearranged.

Place Value Understanding: Numbers 11-20 are composed of one ten and additional ones.

Step-by-Step Methods

Basic Counting Method (1-20):

  1. Point to the first object and say "one"
  2. Move to the next object and say "two"
  3. Continue sequentially until all objects are counted
  4. State the final number as the total count
  5. For numbers 11-20, recognize they contain one ten plus additional ones

Addition Using Counting (1-20):

  1. Count the first group of objects
  2. Continue counting with the second group
  3. The final number is the sum of both groups
  4. For larger sums, consider grouping into tens

Subtraction Using Counting (1-20):

  1. Count all objects initially
  2. Remove the specified number of objects
  3. Count the remaining objects
  4. The count of remaining objects is the answer

Skip Counting Method (1-20):

  1. Identify the interval (2s, 5s, 10s)
  2. Start with the first multiple
  3. Add the interval to get the next number
  4. Continue the pattern up to 20
Concrete Examples (Simple to Advanced)

Simple Examples (1-10):

  • Counting 7 bears: 1, 2, 3, 4, 5, 6, 7 → Total: 7
  • 5 + 3 = 8: Count 5, then continue to 6, 7, 8
  • 8 - 3 = 5: Start with 8, remove 3, count remaining 5

Intermediate Examples (10-15):

  • Counting by 2s: 2, 4, 6, 8, 10, 12, 14
  • 7 + 8 = 15: Start at 7, count 8 more (8, 9, 10, 11, 12, 13, 14, 15)
  • 14 - 6 = 8: Start with 14, count back 6 (13, 12, 11, 10, 9, 8)

Advanced Examples (15-20):

  • Using number line to visualize addition and subtraction up to 20
  • Counting sets of 5: 5, 10, 15, 20
  • Understanding place value: 17 = 10 + 7
  • Word problems: "If I have 12 toys and get 6 more, how many do I have?"
Tips, Tricks, and Common Pitfalls

Helpful Tips:

  • Use physical objects to make counting tangible
  • Count slowly and deliberately to avoid mistakes
  • Touch each object as you count it
  • Arrange objects in a line to maintain order
  • Practice counting everyday objects during routine activities
  • Group objects into tens to understand place value
  • Use number lines to visualize counting from 1 to 20

Common Mistakes to Avoid:

  • Double-counting the same object
  • Skipping objects during counting
  • Starting over when confused instead of continuing
  • Not recognizing that the last number represents the total
  • Mixing up addition and subtraction concepts
  • Difficulty with numbers 11-19 due to irregular naming patterns
  • Confusion about place value in teen numbers

Effective Tricks:

  • Use fingers for counting when starting out
  • Create songs or rhymes for skip counting
  • Draw tally marks to keep track of counted items
  • Use number lines to visualize operations
  • Group objects in tens to make counting easier
  • Practice "counting on" from a given number
  • Use visual aids like ten frames for numbers 11-20
Key Notes for Memorization

Memory Aids:

  • "Plus" means more (addition), "minus" means less (subtraction)
  • Counting forward = adding, counting backward = subtracting
  • The last number you say is always the answer
  • Every object gets exactly one number word
  • It doesn't matter which object you start with
  • Teen numbers have "teen" ending (13=thirteen, 14=fourteen, etc.)

Quick Reminders:

  • Count with your voice and hands together
  • Check your answer by counting again
  • Use drawings to represent math problems
  • Practice regularly to build fluency
  • Connect math to real-life situations
  • Focus extra attention on numbers 11-20 as they are more challenging

Questions & Answers

Question: My kindergartener is good with numbers 1-10 but struggles with 11-20. How can I help them understand the teen numbers?

Answer: Teen numbers are challenging because they break the naming pattern. Here are strategies:

  • Use ten frames: Show one full frame (10) plus additional dots
  • Explicit teaching: Emphasize that "teen" means "and ten" (thirteen = three and ten)
  • Visual aids: Use base-ten blocks to show one ten stick plus ones
  • Pattern recognition: Point out the pattern in 14, 15, 16, 17, 18, 19

Practice daily with real objects. For example, "We have 10 crackers and 3 more - that's thirteen crackers." Repetition with concrete examples helps build understanding.

Question: My child can count to 20 but has trouble counting backwards from 20. Should I be concerned?

Answer: Counting backwards is more challenging than counting forward, and this is completely normal:

  • Developmental timing: Forward counting typically develops before backward counting
  • Cognitive demand: Backwards counting requires more working memory
  • Practice opportunities: We naturally count forward more often
  • Progressive approach: Start with smaller ranges (10-1, then 15-1, then 20-1)

This skill will develop with practice. Start with smaller numbers and gradually work up. Use songs, games, or countdown activities to make it fun.

Question: How can I help my students who struggle with skip counting beyond 10? They can do 2, 4, 6, 8 but get confused at 10, 12, 14, 16, 18, 20.

Answer: Skip counting past 10 can be challenging because of the place value transition. Try these approaches:

  • Visual patterns: Use number charts to highlight skip counting patterns
  • Grouping: Emphasize that 12 is "twelve" not "one-two"
  • Rhythm and music: Use songs with consistent beats for skip counting
  • Concrete objects: Count groups of objects (pairs of shoes, hands)

Practice skip counting from different starting points (start at 3 and count by 2s: 3, 5, 7, 9, 11, 13...). This builds flexibility and deeper understanding.