CCSS.Math.Content.K.OA.A.3
The standard
Decompose numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and record each decomposition by a drawing or equation (e.g., 5 = 2 + 3 and 5 = 4 + 1).
Common Core State Standards for Mathematics · Operations and Algebraic Thinking
What this standard means
Students need to break a number up to 10 into two parts in more than one way. They should use counters, cubes, drawings, fingers, or ten-frames to show the parts, then record what they made with a picture or equation.
Mastery looks like a child saying, “6 can be 1 and 5, 2 and 4, 3 and 3,” and showing each with objects or drawings. Students often get stuck thinking there is only one right pair, losing count after moving objects, or writing equations that do not match their model.
Ways to teach it
- Give each student 7 two-color counters and ask them to shake, spill, sort by color, and record each pair they make.
- Ask, “How many ways can we make 8 with two parts?” and have students draw three different answers in math journals.
- Show 5 cubes split into two groups, then ask students to circle the matching equation from three choices.
- Use snack pieces, such as 10 crackers, and ask students to show two ways to share them between two plates.
Plan a lesson for CCSS.Math.Content.K.OA.A.3
Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.
Related standards
- CCSS.Math.Content.K.NBT.A.1
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decompositio...
- CCSS.Math.Content.1.OA.C.6
Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + ...
- CCSS.Math.Content.4.NF.B.3b
Decompose a fraction into a sum of fractions with the same denominator in more than one way, recording each decomposition by an equation. Justify decompositions...
- CCSS.Math.Content.K.OA.A.4
For any number from 1 to 9, find the number that makes 10 when added to the given number, e.g., by using objects or drawings, and record the answer with a drawi...