Count On Within 20 is a free printable Grade 1 math worksheet on counting on three or four from a larger start, within twenty, aligned to Common Core standard 1.OA.C.5. It prints 13 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two students in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.
1.OA.C.5
Work out each answer.
LessonPrint · 1.OA.C.5 · Set 1 · free to copy for classroom use
Set 1. Prints on its own sheet.
It practices counting on three or four from a larger start, within twenty — 13 questions for Grade 1, all on Common Core 1.OA.C.5: Count on to add, and count back to subtract. The instruction to students is “Work out each answer”, and the answer key follows on the next sheet.
CCSS.MATH.CONTENT.1.OA.C.5 — 1.OA.C.5, under Operations & Algebraic Thinking for Grade 1. The published standard reads: “Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).” The worksheet assesses that standard rather than a paraphrase of it.
Count On Within 20 is written for Grade 1, typically ages 6-7. It is one of the sheets on 1.OA.C.5, so it suits any student working at that standard — including older students revisiting it and younger ones working ahead.
Yes. All 13 answers are generated from the same problems as the questions, so the key cannot drift out of step with the sheet. It starts on a fresh sheet of paper, after the questions, so it is not handed out with the class by accident.
25 — one per student, and all 25 ask different questions. Set 1 downloads the whole class as a single PDF. Every version is fixed to its own address, so a sheet printed today holds the same problems when you reopen it next week.
Yes. Count On Within 20, its answer key and its 25 versions are free to print and photocopy for your own class, with no account, no email capture and no subscription at the download step. Please do not resell them or republish them as your own.
Yes — “Counting On and Counting Back” is a 40-minute Grade 1 plan for 1.OA.C.5, timed section by section, with the misconceptions to expect and an exit ticket. Count On Within 20 is the practice that follows it.
Count on to add, and count back to subtract.
Teaching this next? Counting On and Counting Back is the 40-minute plan for it, with the misconceptions to expect.
Last reviewed 2026-09-05. Aligned to 1.OA.C.5 of the Common Core State Standards for Mathematics.