Take three hands-up answers, not open call-outs. Listen for pupils reaching for both a letter and a number — the moment someone says one without the other is the moment the lesson exists to fix.

• C4, point along to column C, then down to row 4; say the reference in that order.
• B2 — a different square; ask the class which comes first, the letter or the number, before you read it.
• Star at D3 — read it the same way: column D across, then row 3 down. Ask the class to say the whole reference back to you.

Talk this one through together — pupils take turns at the board and the class agrees or corrects out loud.

Send an individual pupil up to tap the square an object sits in; the interactive reveals the reference and the class checks the letter came first. Then reverse it: call a reference and ask a pupil to find that square. Watch for anyone reading the number before the letter — that is the slip to catch on the spot.

This is the practice round — 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.

Point out at the start that this grid reaches across to column F and down to row 6, so it is taller and wider than the copybook grid. The last one, B6, uses that taller grid — the row number goes past four, so hold out for pupils to read the number carefully after the letter. On a wrong answer, ask did you read the letter across before the number? before revealing.