Worksheet Library / Number Sense
Counting Numbers 10–20 · Counting Numbers 10–20 · Complete the Number Sequence
Focus: Completing counting sequences from 10 to 20. Use the neighboring numbers to locate the missing value.
Use New Numbers to make another set. Choose Worksheet or Answer Key, then use the worksheet’s Print button.
Teaching Notes
Focus: Completing counting sequences from 10 to 20. Use the neighboring numbers to locate the missing value.
Before You Begin
- Say number names in order.
Teaching Steps for Parents and Teachers
- Read the numbers in order.
- Find the counting step between consecutive numbers.
- Continue the sequence through the blank and check both neighboring values.
Worked Examples
Complete the sequence: 17, 18, □, 20
- The numbers increase by 1 each time.
- The number after 18 is 19, followed by 20.
Answer: 19
Common Mistakes and How to Help
Changing the tens digit or skipping a number while counting across 19 to 20.
Count aloud from 18 to 20. Which number is between them?
Questions to Check Understanding
- How does the sequence change each time?
- What number comes after 18?
- Does your answer make the sequence count in order?
Practice Advice
Work through the example together. Ask the learner to explain the first two problems, then try three independently. Review the first incorrect step before assigning more practice.
Next Practice
- Use New Numbers to practice the same skill with different values.
- If the learner needs help, return to the example and model each step before trying again.