Take three hands-up answers, not open call-outs. Give a few seconds of quiet think-time first.

Mark 340 between 300 and 400 on a quick line on the board and ask which hundred is it closer to? — don't confirm yet, that is the lesson.

320: two steps past 300, tens digit 2 is small, stays down at 300.

380: ask which hundred it is nearly touching before revealing; tens digit 8, rounds up to 400.

Before the third, ask them to predict what happens when a number sits exactly in the middle.

350: the one that catches them. Pause on exactly halfway, leaning neither way. Name the halfway rule: a halfway number always goes up, so 350 rounds to 400.

This round is for talking it through together — pupils take turns at the board and the class agrees or corrects out loud.

For each number, ask which two hundreds is it between?, then what is the tens digit?, then which way it rounds. On 290 draw out that even though the tens digit 9 belongs to the 200s, it rounds all the way up to 300. On 750, pause on the halfway rule before revealing.

These are the practice questions — pupils take turns at the board, check each answer, and the class confirms before moving on. Keep the board work brisk rather than over-explaining.

• 230 — tens digit 3, rounds down to 200.
• 460 — tens digit 6, rounds up to 500.
• 550 — the halfway case, rounds up to 600.
• 970 — tens digit 7, rounds up to 1,000; draw out that the next hundred is a whole thousand.