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Grade 1 Math: Decompose Numbers

6 printable 1st Grade math worksheets on Decompose Numbers. The first three are free to download; All Access opens all 6.

Practice pages support a program; they are not the lesson. These sheets reinforce Building Number Sense Grade 1, the sequenced K–5 math series from Faith Thinkers. See every program →

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3 of 6 free · Unlock 3 more with All Access

Decompose Numbers Teens 1 Free Sheet 1 of 6
Decompose Numbers Teens 2 Free Sheet 2 of 6
Decompose Numbers Teens 5 Free Sheet 3 of 6
1st Grade math worksheet — Decompose Numbers Teens 3
Decompose Numbers Teens 3 All Access
1st Grade math worksheet — Decompose Numbers Teens 4
Decompose Numbers Teens 4 All Access
1st Grade math worksheet — Decompose Numbers Teens 6
Decompose Numbers Teens 6 All Access

Teaching Decompose Numbers

What it is

These pages ask what goes with ten to make a teen number: 10 + __ = 16. The ten is already there, so the child supplies the ones.

When a child is ready

Ready once teen numbers have been built as a ten and some ones.

If they struggle

If the child adds the two numbers instead of finding the missing part, build 16 as one ten stick and loose cubes and count only the loose ones. After a few, point out that the answer is the second digit of the total, and check that shortcut against the blocks.

This skill in other grades: Kindergarten · Grade 2 · Grade 3 · Grade 4 · Grade 5