Goal: sort familiar large paper shapes by an observable edge and explain one choice. Proposed code: AC9MFSP01. Prepare: practice shape collection; neutral colours; Card 101.
- Notice · 3 min. Show a circle and triangle of the same colour. Ask what could be checked about their edges, without asking for names first.
- Model · 4 min. Trace circle's continuous curved boundary and a triangle's straight side; place each in a labelled group.
- Guide · 5 min. Children trace a square and oblong card and add them to the straight-edge group. Check by touching or following a high-contrast outline.
- Independent sort · 7 min. Give a new-sized circle, triangle, square and oblong. Child sorts and explains one choice by edge, not colour or size. Preserve first placement.
- Challenge · 4 min. Ask if turning the triangle changes whether its sides are straight. Child tests by rotating the same card.
- Exit · 2 min. Ask for a reason a circle is in the curved group. If only the name is given, model tracing and recheck a new outline tomorrow.