Loading preview...

Skills Covered

  • Write all four facts with sums to 20
  • Apply fact family concepts to larger numbers
  • Build fluency with teen number addition and subtraction
  • Strengthen place value understanding
  • Develop strategies for crossing 10
  • Prepare for multi-digit operations

How to Use This Worksheet

Students examine each fact family triangle with sums up to 20 and write all four related equations. Working with larger numbers challenges students to apply their understanding of fact family relationships beyond the basics.

In the Classroom

Use after students are fluent with facts within 10. This is a natural progression that builds toward 2nd grade fluency expectations. Pair with number line or hundreds chart for students who need visual support.

At Home

If your child struggles with the larger numbers, practice skip-counting from the smaller number up to the sum. For subtraction, count back from the larger number. These strategies build confidence.

Tips for Success

  • Encourage students to use making-10 strategies for sums over 10
  • Allow use of a number line for students who need support
  • Celebrate when students recognize patterns across problems
  • Use the answer key for self-checking

Common Core Standards Alignment

This worksheet supports the following Common Core State Standards for Mathematics:

  • 1.OA.C.6 - Add and subtract within 20, demonstrating fluency within 10
  • 2.OA.B.2 - Fluently add and subtract within 20 using mental strategies

Fact Families Within 20 - Write All

1st - 2nd 1 worksheet + answer key

Write all four addition and subtraction facts for each fact family with sums within 20. Extends fact family practice to larger numbers.

Want to customize? Open in Fact Families Generator to change range and difficulty →

What’s Included

  • 1 fact family worksheet
  • Sums within 20
  • Write-all-4-facts format
  • Triangle diagram layout
  • Answer key included