Give five seconds of quiet think-time, then take three hands-up answers. Listen for anyone who says five plus five plus five or three fives rather than counting all fifteen — that is the seed of the whole lesson. Don't confirm the answer yet; hold it for the model step.

Example 1, 3 rows of 4: point along one row, four, then four and four and four is three fours. Write 4 + 4 + 4 = 3 × 4 = 12 beside it.

Example 2, 5 rows of 2: ask more or fewer tiles than the last one, pause for a prediction before revealing. Read as five twos, 5 × 2 = 10.

Example 3, the same ten tiles turned: this is the key one, slow right down. Tall array on left reads 5 × 2, wide array on right reads 2 × 5, count both to get ten and ten. Pick up your ten real tiles laid as 5 by 2, give a quarter turn so they sit as 2 by 5, set beside the on-screen wide array. Say plainly you only turned them, none added, none taken away. Land that 5 × 2 and 2 × 5 both give ten.

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

Keep the watching class working. Before each array is built, ask the whole class to predict the total on their thinking (a quiet count of a few seconds), then take two hands-up answers before the pupil at the board reveals it. After each turn, do a quick turn-and-name: name the multiplication for what is on the board now, two more hands up. That way every array reveal has the whole room predicting and answering, not just the pupil at the board.

Insist every pupil says the array two ways — the repeated addition first (3 and 3 and 3 and 3), then the multiplication (4 × 3). Revoice a strong turn-and-check: so when Aoife turned it, the tiles were the same, so the answer had to be the same. Watch for pupils who recount every tile after turning — prompt do you need to count again, or do you already know?

These are the practice questions — pupils outline each rectangle on their own squared paper and check the count against the multiplication; the class confirms each answer aloud before moving on. Keep the board work brisk rather than over-explaining.

The escalation is deliberate: the last two rectangles are too big to count comfortably one square at a time, so pupils feel why the multiplication shortcut is worth having. The equal-product pair is genuine here — 3-by-8 and 4-by-6 both give 24 — so a callout of which two of your rectangles share the same total? pays off and lands the commutative idea again. For the stretch, pupils can also make a new rectangle that gives 24, such as 2-by-12.