Take three hands-up answers, not open call-outs. Write each suggested two-digit number on the board and read it aloud as so many tens and so many units (e.g. twenty-four is two tens and four units). Give five seconds of quiet think-time before any hands go up.

Walk each example aloud, one at a time, narrating the tens column first, then the units.

• 24 — point to the two ten-rods, then the four cubes; say two tens and four units.
• 40 — this is the one with a question on screen. Take two or three hands-up answers, then confirm: four tens and no units make forty. Emphasise the empty units column.
• 7 — emphasise the empty tens column; only units here.
• 86 — read it as eight tens and six units, then say the whole number.

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

Call a number under 100, send one pupil up to build it, then ask the class how many tens and how many units? before confirming. Rotate four pupils through. Between turns, revoice a pupil's answer back to the room (so two tens and four units is twenty-four) to keep the watching class thinking. Watch for the slip where a pupil builds the units count as ten-rods (e.g. building 24 as four rods and two cubes) — head it off by asking which column comes first when we read left to right.

This round is the practice bank — 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.

For each target ask how many tens and how many units make this number? before the pupil builds. Watch 99 closely — nine ten-rods and nine cubes is the high end and pupils sometimes lose count of the rods; have the class count the rods aloud in tens (10, 20, 30…). Fast finishers watch the board and mouth the tens count.

Recap the two columns (tens on the left, units on the right) and that an empty column still holds a place. Preview the hundreds column briefly without teaching it yet.