Take three hands-up answers, not open call-outs. Listen for anyone who compares the total prices (€2.40 vs €3.20) rather than the price of one pot — that is the exact trap this lesson unpicks, so let it sit rather than correcting it now.

First tag (yoghurts): ask which looks better before the class looks at the interactive. Let a few pupils back the cheaper-looking €2.40 pack, then show both land on 40c (€2.40 ÷ 6 and €3.20 ÷ 8). Point: total price alone cannot decide it.

Middle tag (lunch) is the full worked method. Write both divisions on the board with the class before checking the interactive: €6.00 ÷ 4 = €1.50 per sandwich; €8.40 ÷ 6 = €1.40 per sandwich. The 6-pack wins by 10c per sandwich. Watch for pupils dividing price by price, or subtracting totals, instead of price ÷ pack size.

Third tag (weight): compare the price of one 100 g piece. A 1 kg block is ten 100 g pieces and a 250 g block is two-and-a-half. Pause on the two divisions (€4.50 ÷ 10 = 45c; €1.20 ÷ 2.5 = 48c). The dearer-looking block is actually cheaper for the same 100 g. Ask why equal 100 g pieces make the packs fair to compare.

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

Have the class predict the per-bar price before anyone taps reveal (€3.60 ÷ 3 = €1.20; €4.80 ÷ 4 = €1.20 — a tie, which surprises pupils who expect the bigger pack to always win). Watch for pupils dividing price by price instead of price by size.

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.

The eggs and juice fall cleanly. For the pasta, cut both packs into 100 g pieces first (500 g is five 100 g pieces, 1 kg is ten): 90c ÷ 5 = 18c per 100 g against €1.70 ÷ 10 = 17c per 100 g, so the big pack wins narrowly. The kitchen roll is the closest of the counted items: 80c per roll vs 70c per roll — have the class predict before revealing, as the smaller pack tempts them.