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Day 13 · Twenty groups and three groupsYear 5 Maths · T1 W3–4 · Day 13 lesson

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Year 5 / Mathematics / Term 1 / Weeks 03 04

Part of the full two-week lesson sequence. Check the pack guide and taught point before teaching.

Open for this lesson: Pack guide · Sources and materials · Worked swaps · Aids and text routes.

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Teacher copy: This page may include teaching prompts or answer keys. Answer keys in this public library can be viewed by anyone. Give learners a clean prompt, use checks as formative evidence, and change a case locally when prior access matters.

Fresh learner checks

Success: split a two-digit multiplier into tens and ones, then combine partial products. Prepare: partial-products mat or its text/tactile build. Codes: AC9M5N06.

  1. Recall · 2 min. Ask what ×20 means. Key: twenty groups/two tens of the number, not merely ×2.
  2. Model · 5 min. Write 128×23=128×20+128×3=2,560+384=2,944. Put 2,560 under the twenty groups row and 384 under three groups; align the sum by place. Compare with a loose 130×20=2,600, noting why the exact can be higher.
  3. Guide · 6 min. Calculate 64×36 = 64×30 + 64×6 = 1,920+384=2,304. Ask child to audit the false partial 64×30=192 and restore the tens value.
  4. Choose · 7 min. Day 13 A/B/C route: two-digit multiplication in a new fictional domain. Learner selects mat, expanded notation, grid or another efficient correct method and labels the tens product.
  5. Exit · 3 min. “Would 294 be plausible for 128×23?” Key: no; 128×20 alone is 2,560. Ask for a lower bound.
  6. Record · 2 min. Save the two partial products and the child's check, not only the final numeral.

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