Take three hands-up answers and acknowledge each without confirming which is right. Hold the question open: the lesson is going to give the class three different strategies for settling it.

Pacing

Spend roughly two-and-a-half minutes per example, with a short pause between each. The point is for the class to see the strategy in the strips, not just take notes from the board.

Beat by beat

• Opening note: read the 'Quickest case' framing aloud. Say 'before we go any further: if the bottoms are already the same, the comparison is done. Just count the tops.' This lands in 20 seconds and means the class can spot matching-bottom pairs immediately later on.
• Example 1: trace the two strips with your finger. Say 'the strips look close, so we rewrite. Three quarters becomes nine twelfths. Five sixths becomes ten twelfths. Now we can read it.' Close by asking the class: 'what was the strategy?' The answer is common denominator.
• Example 2: same move, common denominator fifteen. Ask the class to predict each rewrite before you reveal it. Ask again at the end to name the strategy: common denominator.
• Pause before Example 3: say 'common denominator always works. But there are shortcuts worth knowing.' This signposts a strategy change.
• Example 3: this is the lock-in for the half-benchmark. Trace the halfway mark on each strip. Say '2/7 is under the half. 5/9 is over the half. We are done.' No common denominator needed. Ask the class to name the strategy: benchmark to one half.
• Pause before Example 4: say 'one more shortcut. Watch the tops.' Contrast it with Examples 1 and 2 deliberately: 'there we rewrote because the bottoms didn't match. Here the tops already match, so we don't need to rewrite at all.'
• Example 4: point to the matching numerators (both 4). Say 'same number of pieces. Bigger pieces win. So the smaller bottom wins.' Name the counter-intuitive bit out loud: 'usually a bigger bottom would mean smaller pieces — and that is exactly the rule that proves it.' Ask the class to name the strategy: common numerator.

One comparison, talked through together. A pupil comes to the board and shades 5/8 on the eighths strip and 2/3 on the thirds strip while the class calls each shaded count.

Run the spotting protocol first. Ask: 'do the tops match?' (No — 5 and 2.) 'Is one above half and one below?' (No — both above one half: 5/8 is just over, 2/3 is well over.) So the shortcuts are ruled out and common denominator (24) is the move. Work the rewrite on the IWB pen alongside the widget: 5/8 = 15/24 (multiply top and bottom by 3) and 2/3 = 16/24 (multiply top and bottom by 8). The class reads 15/24 vs 16/24 and confirms 2/3 is the slightly bigger fraction. The strips on screen are the visual sanity check; the rewriting work is on the board.

Listen for the 'longer-shaded strip is the bigger fraction' revoice — that's the visual proof the maths is doing.

This round is the practice bank — 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.

• 1/2 vs 3/4: common denominator 4, or spot that 1/2 = 2/4. Easy opener.
• 7/8 vs 11/12: common denominator 24. Have the class rewrite aloud (21/24 vs 22/24) before the pupil at the board taps Check.
• 3/4 vs 4/7: common denominator 28. Counter-intuitive because 4/7 looks substantial before you compute — but 21/28 vs 16/28 settles it.
• 3/8 vs 7/10: 'one is under the half, one is over — we're done'. Resist a common denominator if a pupil suggests it; the half-split is the lesson here.
• 5/8 vs 5/11: point to the matching tops, then to the strips. Smaller bottom = bigger pieces = bigger fraction, so 5/8 wins. Counter-intuitive for pupils still anchored on 'bigger bottom number means bigger fraction'.