Slide the tiles one at a time and hold out for the two rules: no gaps, no overlaps. Take two or three hands-up answers on "what are we measuring now that is different from the distance around?" — don't name "area" yet; let it come from the class.

• 3-by-4 patch — count the twelve one by one; then ask if anyone spotted a quicker way (the rows). Hold that thought for tomorrow's rows-by-columns lesson; today we count.
• L-shape — the trap is counting a square twice at the corner, or missing one. Point round the bend as the class counts to five.
• Two halves — say two half-squares join to make one whole square unit. This is the fact they need for the staircase in the challenge.

End the beat by naming it: this is area, measured in square centimetres, written cm².

Outline a shape on the board over the grid, then hand over to one pupil to tile and count aloud. Rotate four pupils across the prompts, and keep the class checking the count rather than the tiling: "did we miss one? did anyone count a square twice?". The graded versions come next in the Class Challenge, so leave Check alone here.

Class Challenge: pupils take turns at the board, tile each outline, and the class confirms before moving on. Keep the board work brisk rather than over-explaining.

Individual pupils tile each outline; the class predicts the count before the last tile lands. The staircase is the key one in the sequence — hold out for the two half-squares being joined into one whole (its area is a whole number, not a "and a half"). Fast finishers who are not at the board watch and mouth the next count; the 10-square open task is the stretch to name aloud. Groups with square tiles at their desks can verify each outline by hand.

Keep the recap to the three points. The forward hook to rows-by-columns links straight to the next lesson.