Take three hands-up answers, not open call-outs. Steer the class toward noticing that all three have four sides but the sides and corners differ. Keep it brief — this is just the hook.

Walk each shape aloud, one at a time. For each, ask the class to predict the property before you reveal it. The work splits into three small groups so the five families are not loaded all at once.

• Square — four equal sides, four square corners. Point out it ticks every box.
• Rectangle — opposite sides equal, four square corners; emphasise the sides are not all equal. Pause here for the first quick check before moving on.
• Rhombus — four equal sides but the corners are leaning, not square.
• Parallelogram — opposite sides equal and parallel, leaning corners. Pause here for the second quick check.
• Trapezium — drive home that it has just one pair of parallel sides, the property that sets it apart.

The make-or-break idea today is checking each property in turn: equal sides, parallel sides, right angles. Use the on-board line defining 'parallel' so the word lands before pupils rely on it.

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

The cards are pictures of shapes, not words, so pupils must inspect each one rather than read off an answer. Insist that each pupil says how they decided: "four equal sides and square corners, so it's a square". Watch for the rhombus-versus-square trap (a leaning four-equal-sided shape is a rhombus) and the parallelogram-versus-rectangle trap (a leaning shape with no square corners is a parallelogram). Several cards are drawn leaning or rotated so pupils cannot guess from orientation alone.

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.

Real straws or strips are at pupils' desks. Lead the build at the front and have the class follow with their own straws. Allow time for joining the straws — this is the part that takes longest. The key insight: leaning a square keeps the sides equal but loses the square corners (square becomes rhombus); leaning a rectangle keeps opposite sides equal but loses the square corners (rectangle becomes parallelogram). For the trapezium, only one pair of sides should run perfectly parallel. If time is short, treat the square-to-rhombus build as core and the rectangle-to-parallelogram and trapezium as stretch.

Keep this brisk — a quick recap of the five families and the square-as-special-rectangle idea, then a one-line look ahead to polygons.