Show the half-butterfly image as pupils settle. Take two or three hands-up answers, not open call-outs. Don't reveal the rule yet — just let them sense that the missing spot has to sit the same distance from the line, on the opposite side.

Walk each example aloud, one at a time, pointing at the squares and counting from the line each time.

• One out — establish the count-from-the-line move.
• Three out — say 'one, two, three' on each side so the class hears the matching count.
• The L-shape — before you confirm, ask the class to predict where the L will land; stress that you reflect each square separately, not the L as a lump.
• On the line — the trap: a square sitting on the line does not move. Ask the class to predict before you confirm.

This is a static display — point and narrate, do not drag. The L-shape and on-the-line examples are the hardest, so keep the earlier two brisk and slow down here.

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

Place two or three squares on one side, then call a pupil up to reflect each one. Ask the class to count the distance aloud before each placement: 'how many squares out is this one?' Watch for the common slip of placing the mirror one square too near or too far from the line — catch it by re-counting together. Rotate a few pupils through the placements.

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.

The square-on-the-line round is the make-or-break check: that square sits on the line and does not move. Re-count distances aloud whenever a placement wobbles, and ask the class to predict before confirming each answer.