Worksheet Bench
1st GradeMixed Review1.OA.D.8

Fact Families Within 20 Worksheets for 1st Grade

These fact families within 20 worksheets give parents and teachers focused, repeatable practice for 1st Grade learners. Write related addition and subtraction equations for the same three whole numbers. Choose a fixed-seed sample or make a fresh printable without creating an account.

Learning objective: Write related addition and subtraction equations for the same three whole numbers.
Reproducible fixed seeds

Three free worksheet samples

Open a sample to preview all questions, make a fresh version, or download the worksheet and answer key.

Fact Families Within 20
Sample 1 · Seed leaf-19-1-fact-families-within-20-sample-a7
1. Use the addition and subtraction fact family for 10, 0, and 10. Complete: 10 − 0 = ___
2. Use the addition and subtraction fact family for 4, 11, and 15. Complete: 15 − 4 = ___
3. Use the addition and subtraction fact family for 7, 12, and 19. Complete: 7 + 12 = ___
4. Use the addition and subtraction fact family for 11, 0, and 11. Complete: 0 + 11 = ___
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Fact Families Within 20
Sample 2 · Seed leaf-19-1-fact-families-within-20-sample-m3
1. Use the addition and subtraction fact family for 1, 4, and 5. Complete: 5 − 1 = ___
2. Use the addition and subtraction fact family for 6, 14, and 20. Complete: 20 − 14 = ___
3. Use the addition and subtraction fact family for 11, 2, and 13. Complete: 2 + 11 = ___
4. Use the addition and subtraction fact family for 3, 5, and 8. Complete: 3 + 5 = ___
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Fact Families Within 20
Sample 3 · Seed leaf-19-1-fact-families-within-20-sample-z9
1. Use the addition and subtraction fact family for 2, 0, and 2. Complete: 0 + 2 = ___
2. Use the addition and subtraction fact family for 3, 1, and 4. Complete: 4 − 1 = ___
3. Use the addition and subtraction fact family for 3, 14, and 17. Complete: 3 + 14 = ___
4. Use the addition and subtraction fact family for 6, 1, and 7. Complete: 1 + 6 = ___
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One fixed-seed example

How to approach this skill

Problem: Use the addition and subtraction fact family for 10, 0, and 10. Complete: 10 − 0 = ___

Answer: 10

Strategy: Name the problem type before solving so the operation or representation is chosen for a mathematical reason. This example supports the page objective: Write related addition and subtraction equations for the same three whole numbers.

How to use this worksheet

  • Use the first set as a brief diagnostic, then target practice to the errors found. For this fact families within 20 set, begin without a timer.
  • Ask learners to name the strategy they chose as problem types change. Regenerate only when the learner is ready for another arrangement of the same objective.

Begin with the easy setting when the strategy is new, use standard for independent practice, and reserve challenge for a learner who can explain the method accurately.

Common mistakes to watch

  • Continuing one operation when the problem type has changed. Watch for this specifically during fact families within 20 practice.
  • Rushing through familiar-looking items without reading symbols or units. Use the worked correction as the next teaching example.

Use the answer key to find a pattern, then ask the learner to explain one corrected example rather than repeating an entire set immediately.

Standards reference

Skill alignment

Alignment labels identify the primary skill practiced. A worksheet is supplemental practice and does not assess every part of a standard.

Planning help

Frequently asked questions

What does this 1st Grade Fact Families Within 20 worksheet practice?

Write related addition and subtraction equations for the same three whole numbers.

How should adults use the Fact Families Within 20 printable?

Start with one untimed set, review the learner's strategy, and use the answer key to discuss errors. Generate a new fixed-seed set only after the current skill is understood.

Does the Fact Families Within 20 download include answers?

Yes. The free PDF can include an appended answer key, or the answer key can be downloaded separately for adult use.

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Automated QA passed · Updated 2026-07-15

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