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Day 16 · Open a hundred bundleYear 2 Maths · T1 W3–4 · Day 16 lesson

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Year 2 / Mathematics / Term 1 / Weeks 03 04

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

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Codes: AC9M2N01, AC9M2N02. Goal: represent a three-digit quantity and exchange one hundred for ten tens without changing the total. Prepare: 2 hundred squares, 14 ten-strips, 6 singles, mat.

  1. Invite · 2. Build 246 and ask, “If I open one hundred bundle, is it still 246?” Invite prediction.
  2. Model · 5. Name 2H 4T 6O, then replace one H with ten T. Count 1H 14T 6O = 100 + 140 + 6 = 246; leave both drawings visible. Say “the grouping changed; the number did not.”
  3. Guided · 6. Build 324. Learners tell you to exchange one H. Together record 2H 12T 4O. Ask them to verify with 200 + 120 + 4.
  4. Choice · 6. Choose a D16 card. Child makes/sketches both groupings and says why they are equal. Partner tests by counting tens, not copying digits.
  5. Exit · 4. Ask for another grouping of 231 after opening one hundred; check 1H 13T 1O. If a child writes 1H 3T 1O, put the missing ten strips back one by one.
  6. Note · 2. Record independent exchange, prompted exchange or not yet observed.

Access/home/extension: Use folded paper bundles or sketches; partner manipulates on request. Home: 10 dots per strip on scrap paper. Extension: open both hundreds and explain 24T 6O for 246.

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