CCSS.Math.Content.1.OA.A

Math1st GradeOperations and Algebraic Thinking

The standard

Represent and solve problems involving addition and subtraction.

Common Core State Standards for Mathematics

What this standard means

Students need to make sense of add-to, take-from, put-together, take-apart, and compare problems. They should use objects, drawings, fingers, ten-frames, number bonds, and equations to show what is happening. They also need to explain whether they are adding or subtracting and why.

Mastery looks like choosing a strategy that matches the story, not just grabbing numbers. Students can write equations with the unknown in different places, like 8 = 5 + __. Common trouble spots are compare problems, missing-start problems, and thinking the equal sign means “the answer comes next.”

Ways to teach it

  • Give pairs counters and story cards, then have them act out each problem and record a matching drawing and equation.
  • Ask, “How do you know if this story is asking us to add or subtract?” and have students justify with partner talk.
  • Show one word problem and three equations, then have students circle the matching equation and explain their choice.
  • Use lunch count or classroom supply needs to write real addition and subtraction problems from the day.

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Related standards

Standard text verified against corestandards.org on July 10, 2026.

Page updated July 10, 2026.

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