Mystery Bureau › Grade 3 standards › 3.OA.C.7
📘 Common Core · 3.OA.C.7 · Grade 3
This is the standard third grade is built around, and it asks for two different things. Fluency means using relationships — that 6 × 7 and 42 ÷ 6 are the same fact seen from two sides. From memory means recall without a strategy. A student who reconstructs 7 × 8 by doubling has met the first half and not the second, and the difference shows up immediately in fourth grade.
Quoted verbatim from the Common Core State Standards for Mathematics. Nothing here is paraphrased.
| 3.OA.C.7 | Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers. |
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In plain English: Multiply and divide within 100 fluently, and know all products of two one-digit numbers from memory by the end of third grade.
Each one runs in the browser with no account and nothing stored. Five questions apiece.
Real output from the activities above — not written for this page, drawn from the same pools a student gets. The numbers are rebuilt on every attempt.
| Cut every beam that is a multiple of 3 | 6, 27, 18 (3 of 6 beams) |
| Cut every beam that is a multiple of 6 | 36, 24, 48 (3 of 6 beams) |
| Cut every beam that is a multiple of 7 | 56, 42, 28 (3 of 6 beams) |
| 4 airlocks each hold 6 oxygen tanks. How many tanks in all? | 24 |
| 5 airlocks each hold 7 oxygen tanks. How many tanks in all? | 35 |
| 8 airlocks each hold 9 oxygen tanks. How many tanks in all? | 72 |
| Connect the stars counting by 5s — start at 5 | 5 → 10 → 15 → 20 → 25 |
| Connect the stars counting by 8s — start at 8 | 8 → 16 → 24 → 32 → 40 |
| Connect the stars counting by 3s — start at 3 | 3 → 6 → 9 → 12 → 15 |
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