Counting to 20

Grade 1 Easy Counting Cardinality

Learning Objectives

  • Count from 1 to 20 without skipping
  • Match numbers to sets of objects up to 20

Concept Explanation

Being able to count from 1 to 20 is a foundational skill in early math. Students learn to label each object in a set with a unique number name (1-to-1 correspondence) and recite the counting sequence in the correct order. Mastering this lays the groundwork for understanding larger numbers later.

Worked Examples

Example 1

Problem: Count the stars (imagine 7 stars).
Solution: 7
Explanation: Assign each star a number from 1 to 7.

Example 2

Problem: What comes after 11 when counting up?
Solution: 12
Explanation: 12 is the next number in the sequence after 11.

Example 3

Problem: If you have 15 sticks and get 4 more, how many do you have in total?
Solution: 19
Explanation: You continue counting: 16, 17, 18, 19.

Common Errors

ErrorCorrectionReason
Skipping numbers (e.g., 1, 2, 4)Recite each number carefullyMissing a number breaks the correct counting order.
Mixing numerals and words (e.g., “1, 2, three”)Practice uniform counting methodsConsistency in naming helps avoid confusion.
Forgetting zeroInclude 0 as a valid numberZero is important for place value and future math.

Practice Problems

  1. Problem: Count from 1 up to 5 out loud.
    Solution: 1, 2, 3, 4, 5
  2. Problem: What number comes after 9?
    Solution: 10
  3. Problem: How many objects are here: ● ● ● (3 circles)?
    Solution: 3
  4. Problem: Is 15 bigger than 10?
    Solution: Yes, 15 is greater.
  5. Problem: What number comes right before 20?
    Solution: 19

Real-World Application Example

When singing the “Counting Song” or playing “Hide and Seek,” you often count up to 20 to give others time to hide. Mastering this sequence ensures no one is rushed or missed.

Related Concepts