Take three hands-up answers, not open call-outs. Don't confirm or correct yet — let the doubt sit. The 2/7 claim is the misconception this whole lesson dismantles, so resist explaining; just gather a couple of gut reactions and move on.

Common denominator is the make-or-break move: name it aloud every time before adding or subtracting.

1/4 + 1/3: strips are different sizes, so we can't add as they are. Point back to why 2/7 was wrong. Twelfths is the smallest size fitting both quarters and thirds: quarter becomes 3/12, third becomes 4/12, together 7/12.

5/6 - 1/2: only the half needs renaming, since 6 already works for both. Renamed to 3/6, then 5/6 - 3/6 = 2/6. Stress the tidy-up: 2/6 is correct but 1/3 is tidier.

3/4 - 2/3: both become twelfths, 9/12 and 8/12, difference 1/12. Ask: does this need simplifying? No, 1/12 is already simplest.

This round is for talking it through together — pupils take turns at the board and the class agrees or corrects out loud. The strips start blank. Clear the shading after each problem and re-shade for the next pair, so the same four strips carry all three in turn.

• 2/5 + 3/10 — the strips start as 2/5 and 3/10. Ask which fraction needs renaming. Only the fifths do: 2/5 becomes 4/10. Then 4/10 + 3/10 = 7/10, already simplest.
• 1/2 + 1/4 — clear the strips, re-shade a half and a quarter, then rename the half to 2/4 and add to get 3/4.
• 7/8 − 3/4 — clear and re-shade, rename 3/4 to 6/8, take it from 7/8 to leave 1/8.

Listen for pupils who try to add the bottom numbers — send them straight back to the strips so the size mismatch is visible.

These are the practice questions — pupils take turns at the board and the class confirms each answer before moving on. Keep the board work brisk rather than over-explaining.

• The earlier targets land on one renamed denominator; the last two need twelfths.
• The tool checks the final shaded answer only, so the renaming step is confirmed aloud by the class before each Check, not by the interactive.
• While one pupil shades, the watching class agrees or corrects the renaming aloud — that confirmation is their job each turn, so let a short gap sit for it rather than rushing the Check.

Tie the day's work back to the opening pizza: Aoife and Conor ate 7/12 of it together, not 2/7. The renaming habit is the bridge into mixed numbers next lesson.