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Addition Within 20 — Crossing Ten is a free printable Grade 1 maths worksheet on sums that cross the ten boundary, larger addends, aligned to Common Core standard 1.OA.C.6. It prints 9 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 24 of 25 · the same problems every time you open this link.

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One paper per pupil

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Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Addition Within 20 — Crossing Ten

1.OA.C.6

NameDate

Work out each answer.

1.9 + 6 =
2.6 + 9 =
3.7 + 8 =
4.6 + 7 =
5.8 + 8 =
6.8 + 6 =
7.9 + 8 =
8.9 + 9 =
9.7 + 7 =

LessonPrint · 1.OA.C.6 · Set 24 · free to copy for classroom use

Answer key — Addition Within 20 — Crossing Ten

Set 24. Prints on its own sheet.

  1. 1.15
  2. 2.15
  3. 3.15
  4. 4.13
  5. 5.16
  6. 6.14
  7. 7.17
  8. 8.18
  9. 9.14

More practice for 1.OA.C.6

Add and subtract within 20, quickly and accurately within 10.

Teaching this next? Addition and Subtraction Within 20 is the 45-minute plan for it, with the misconceptions to expect.

All Grade 1 worksheets

Last reviewed 2026-09-05. Aligned to 1.OA.C.6 of the Common Core State Standards for mathematics.