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

Related facts: Challenge Page

A free printable subtraction within 20 page for Grade 1 students, built around Related facts.

Related facts: Challenge Page

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

  1. Fill the fact family: 7 − 3 = ___ and 7 − 4 = ___
  2. Fill the fact family: 4 − 3 = ___ and 4 − 1 = ___
  3. Fill the fact family: 7 − 4 = ___ and 7 − 3 = ___
  4. Fill the fact family: 9 − 5 = ___ and 9 − 4 = ___
  5. Fill the fact family: 6 − 5 = ___ and 6 − 1 = ___
  6. Fill the fact family: 7 − 6 = ___ and 7 − 1 = ___

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.

Bring focused, low-prep practice into your classroom or home with this Grade 1 worksheet on Related facts. It targets the Subtraction within 20 strand of the Common Core math standards (CCSS.Math.1.OA) and prints cleanly on a single sheet of letter or A4 paper.

We organize the page so the easier warm-up problems sit at the top and the more challenging stretch questions sit near the bottom, giving students a confidence boost before they reach the harder work. By the end of the page, learners should be able to explain their strategy in a sentence, not just write an answer.

This page works well as morning math, as a center rotation, as a short homework assignment, or as a quick formative check before a quiz. The same one-page format also makes it easy to keep a small folder of completed work as evidence for parent–teacher conferences.

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

Teachers tell us the most useful thing about this Related facts page is that it can be dropped into morning math, into a small-group rotation, or into a homework folder without any pre-teaching. Students can read the directions, look at the first warm-up, and start working without waiting for a grown-up to translate.

This worksheet is aligned to Common Core State Standard CCSS.Math.1.OA and supports the broader Subtraction 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.

If your student finishes this Related facts page quickly and easily, take a look at the next printable in the Subtraction within 20 series. The difficulty climbs gradually so kids meet a stretch problem without getting overwhelmed.

Sample problems on this worksheet

  1. Fill the fact family: 7 − 3 = ___ and 7 − 4 = ___
  2. Fill the fact family: 4 − 3 = ___ and 4 − 1 = ___
  3. Fill the fact family: 7 − 4 = ___ and 7 − 3 = ___
  4. Fill the fact family: 9 − 5 = ___ and 9 − 4 = ___
  5. Fill the fact family: 6 − 5 = ___ and 6 − 1 = ___
  6. Fill the fact family: 7 − 6 = ___ and 7 − 1 = ___

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 Subtraction 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 Subtraction within 20 hub. To see the rest of the Grade 1 work in this strand, visit the Grade 1 · Subtraction within 20 collection.

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