Missing Numbers to 120 Worksheets for 1st Grade

Home › 1st Grade › Math

Download PDF worksheetAnswer key (PDF)Worksheet + answer key (2 pages)

Prints on one US Letter page; the answer key is a separate page. Print at 100% / "Actual size" on US Letter paper. Free for personal and classroom use. Version 1 of 10. Choose another version.

Grade 1MathCounting & Number SenseCCSS 1.NBT.A.1

Skill: Counting on by ones to fill in missing numbers from 21 to 120

Preview of the Missing Numbers to 120 printable worksheet
Page 1 preview (US Letter PDF)

Teaching tips and what to try next

Works best for first graders who count to 100 without help and know the decade names. Saying the numbers aloud while tapping a hundred chart catches slips such as writing 1001 for 101 before they reach paper. Afterward, compare and order numbers in Ordering Numbers and Counting to 120 or see the standard at 1.NBT.A.1.

10 versions, each with its own answer key

Same skill and layout, a fresh set of problems in every version, so children can keep practicing without repeating a page. Problems are not repeated between versions unless a skill has only a small number of possible problems (for example, the addition facts within 10).

Download all 10 versions (one PDF)All 10 answer keys (PDF)

Related worksheets

About this worksheet

First graders are expected to count to 120, starting at any number, and to read and write those numbers. The trickiest spots are the places where the tens change, and the jump past 100, where children often write 1000 instead of 100 or 1001 instead of 101. This first-grade worksheet gives ten rows of counting practice aimed right at those spots.

Each row shows six numbers in order, counting on by ones. Two of the boxes are empty, and children write the missing numbers. The first number in each row is always shown, so children have a place to start. Six rows sit between 21 and 99, and four rows start between 95 and 114, so they cross 100 or count on in the hundreds up to 120. The rows are mixed on the page, so children cannot simply copy the pattern from the row above. Each of the ten versions has new rows and its own answer key.

How to use it: count out loud together first, starting at a number like 96 and going past 100. Point out that after 100 the numbers sound like "one hundred one, one hundred two," and that the last two digits count just like 1, 2, 3. If your child gets stuck at a new ten, such as after 79, ask what comes after 7 tens and 9 ones. A hundred chart on the table is a good helper for the first few rows.

The answer key shows each missing number. For smaller numbers, try our Missing Numbers 1-20 worksheet. To put numbers in order, try our Ordering Numbers and Counting to 120 worksheet.