Answer Key — 2.OA.B.2
For parents and tutors
Do not share with students before practice tests.
Practice Problems — Sets 1–10
| Set | Guidance | | --- | --- | | Set 1 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 2 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 3 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 4 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 5 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 6 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 7 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 8 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 9 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 10 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. |
Practice Problems — Sets 11–20
| Set | Guidance | | --- | --- | | Set 11 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 12 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 13 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 14 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 15 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 16 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 17 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 18 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 19 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. | | Set 20 | Fluently add and subtract within 20 using mental strategies — verify written work and accept reasonable drawings. |
Review tiers 1–10
- Checklists are parent-judged.
- Written items: verify against practice set patterns.
- Standard text: Fluently add and subtract within 20 using mental strategies.2 By end of Grade 2, know from memory all sums of two one-digit numbers.
Practice test scoring
| Tier | Pass guidance | | --- | --- | | 1–3 | Most oral tasks smooth; majority of written correct | | 4–6 | 7/10+ total with clear understanding | | 7–8 | 9/12+ with explanations | | 9–10 | Near-perfect; ready to move on |
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