Write 3,456 on the board and give five seconds of quiet think-time before any hands go up. Take two or three hands-up answers, not open call-outs. You are only fishing for ideas here ("three thousand and the rest", "break it into the columns") — do not confirm or correct yet; the model step builds it properly.

Reveal one example at a time, so only one block is on the board.

3,456: point to each column, name its value, land 3000 + 400 + 50 + 6.

3,400: the key trade. Trade each thousand-block for ten hundred-flats, three thousands become thirty hundreds, plus the four already there gives thirty-four hundreds. Stress the value is unchanged.

2,500: ask how many hundreds before I trade, pause for a prediction. Two thousands trade for twenty hundreds, plus five already there gives twenty-five hundreds.

Make-or-break: renaming rearranges the blocks but never changes the total.

This round is for talking it through together — pupils take turns at the board and the class agrees or corrects out loud. Each number appears in turn in the interactive; the watching class says the column values aloud before you press Check.

Run each of the four values in order:

• 4,050 (partition) — watch for pupils forgetting the empty hundreds column; the answer is 4000 + 0 + 50 + 0; empty hundreds and units.
• 4,700 (rename) — trade four thousands for forty hundreds, add seven: forty-seven hundreds.
• 6,308 (partition) — 6000 + 300 + 0 + 8; the empty tens column is the trap.
• 2,300 (rename) — twenty-three hundreds.

After each build, ask the class the check question: "did renaming change how much it is worth?" Revoice a strong answer: so we only moved the blocks around — the number is exactly the same.

These are the practice questions — pupils take turns at the board, check each answer, and the class confirms before moving on. Each number's operation is named on the board and in the item label, so pupils can see whether to partition or rename. Keep the board work brisk rather than over-explaining.

The point is 9,090: two empty columns (hundreds and units) partitioned as 9000 + 0 + 90 + 0. Ask "did renaming change how much it is worth?" after each. The zeros are where slips happen — get pupils to say each column value aloud, including the zeros, before pressing Check.