Public learning track
Word Problems: Addition and Subtraction Within 100
1st Grade · Math · Open Global Math
9 lessons
Goal
Solve one-step and two-step addition and subtraction word problems across various situation types within 20 and extending to 100.
Featured Diagrams
Word Problems: Add To with Result, Change, and Start Unknown
9 lessons
0 of 9 done
- 1Word Problems: Add To with Result, Change, and Start UnknownUp nextStart
- 2Word Problems: Take From with Result, Change, and Start UnknownPremiumNot started yet
- 3Word Problems: Put Together and Take ApartNot started yet
- 4Word Problems: Compare with Difference UnknownNot started yet
- 5Word Problems: Compare with Bigger or Smaller UnknownNot started yet
- 6Drawing Bar Models to Represent Word ProblemsNot started yet
- 7Two-Step Addition and Subtraction Word Problems Within 20Not started yet
- 8Two-Step Word Problems Within 100Not started yet
- 9Verifying Word Problem Answers with Inverse ModelsNot started yet
Standards Covered
- OGM.2.OA.5Open Global Math Standards 2026™ · Math · Level 2 / Grade 1 (Age 6) · Grade 1Solve one-step and multi-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing within 20 (and extending to 100), formulating number sentences and justifying solutions using concrete, pictorial, and symbolic representations.
- OGM.2.OA.3Open Global Math Standards 2026™ · Math · Level 2 / Grade 1 (Age 6) · Grade 1Understand subtraction as an unknown-addend problem and recognize the inverse relationship between addition and subtraction, utilizing fact families, part-whole bar models, and balance scales to verify computations.
Curriculum Framework
1st Grade · Math · Open Global Math
1
12 lessons
Addition and Subtraction Fact Strategies Within 20
Master addition and subtraction facts within 10 and develop flexible mental strategies within 20.
2
8 lessons
Properties of Addition and Mental Strategies
Apply the commutative, associative, and identity properties to calculate sums within 20 and up to 100.
3
8 lessons
Fact Families and Part-Whole Relationships
Connect addition and subtraction through fact families, bar models, and balance scales.
4
8 lessons
Understanding Equivalence and Equations
Understand the equal sign as balance, evaluate true/false equations, and solve missing-number equations in all positions.
5
9 lessons
Word Problems: Addition and Subtraction Within 100
Solve one-step and two-step addition and subtraction word problems across various situation types within 20 and extending to 100.
6
9 lessons
Equal Groups, Arrays, and Early Multiplication
Build multiplication and division concepts through equal groups, repeated addition, equal sharing, and rectangular arrays.
7
8 lessons
Repeating, Growing, and Cyclical Patterns
Identify, describe, extend, and create repeating, growing, and cyclical patterns using shapes, objects, sounds, and numbers.