Grade 1 Addition within 20 CCSS.Math.1.OA

Adding three single-digit numbers: Word Problems

A free printable addition within 20 page for Grade 1 students, built around Adding three single-digit numbers.

Adding three single-digit numbers: Word Problems

Grade 1 · Addition within 20 · CCSS.Math.1.OA

  1. 9 + 9 + 1 = ___
  2. 5 + 1 + 1 = ___
  3. 6 + 5 + 1 = ___
  4. 2 + 4 + 7 = ___
  5. 3 + 3 + 9 = ___
  6. 3 + 3 + 4 = ___

This is the preview. Hit "Print this worksheet" above to open a clean, ad-free, one-page version with name and date lines and writing space for each problem. A separate answer key prints on the second page for the grown-up. Tear it off before handing the practice page to your child.

Help students build fluency with Adding three single-digit numbers using this Grade 1 printable from our Addition within 20 series. Aligned to CCSS.Math.1.OA, the page mixes routine computation, short word problems, and visual models so kids see the same idea from multiple angles.

Each printable is a single black-and-white page that prints cleanly on standard letter or A4 paper, so teachers and parents can run off a class set or a single copy without wasting toner. Students who finish quickly can flip the page over and write two new problems of their own that target the same skill. It's a powerful retention trick that doubles as a quick formative check.

Strong students can race the clock and aim for a personal best. Students who need more support can work in pairs and explain their thinking out loud, which is one of the highest-leverage moves in elementary math because it forces students to put fuzzy thinking into clear words.

Want a different angle on this skill? Try the matching variants in our Grade 1 · Addition within 20 collection, or jump up to the cross-grade Addition within 20 hub.

We deliberately keep the layout uncluttered: a clean header, generous spacing for kids to show their work, and a problem grid that does not feel overwhelming. Elementary students get tunnel vision on busy pages, and that visual anxiety is often mistaken for a math gap.

This worksheet is aligned to Common Core State Standard CCSS.Math.1.OA and supports the broader Addition within 20 progression that students continue to build through later grades. The same skill is revisited each year with greater abstraction, so the work your student does on this single sheet feeds into the multi-digit and multi-step problems they will see in middle school.

Looking for more Addition within 20 practice? Browse the rest of the Grade 1 collection for related printables that scaffold the same standard from different angles.

Sample problems on this worksheet

  1. 9 + 9 + 1 = ___
  2. 5 + 1 + 1 = ___
  3. 6 + 5 + 1 = ___
  4. 2 + 4 + 7 = ___
  5. 3 + 3 + 9 = ___
  6. 3 + 3 + 4 = ___

How to use this worksheet

Print one copy per child on standard letter or A4 paper. Set a quiet 10 to 15 minute window. Hand your student a sharpened pencil and an eraser, and let them work top to bottom. The first row is a warm-up on purpose. The last row is a stretch on purpose. Sit with them as they finish so any misconceptions surface right away instead of getting practiced into a bad habit.

If your student finishes quickly, flip the page over and ask them to write two new problems of their own that target the same skill. It's a powerful retention move. If they get stuck, pull out manipulatives that match the skill (counters for early addition, base-ten blocks for place value, fraction tiles for fractions) and work through one or two problems together before letting them try the rest on their own.

Common Core alignment

This page targets CCSS.Math.1.OA inside the broader Addition within 20 progression. The skill is introduced earlier in elementary school through concrete representations and revisited each year with greater abstraction. To see how it develops across grade levels, visit our Addition within 20 hub. To see the rest of the Grade 1 work in this strand, visit the Grade 1 · Addition within 20 collection.

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