Goal: describe one-material and two-material constructions without assuming a property. Proposed codes: AC9SFU03, AC9SFI03, AC9SFI05. Prepare: arrow parts, large clean actual samples only if approved, L text, Card 102.
- Label · 3 min. Show actual approved arrows with source/date or paper L cards; do not mix their source labels.
- Compare · 4 min. Read P paper front only and C same paper front plus broad card backing; same outline is a planned control.
- Model · 5 min. Adult distinguishes “two named materials in C” from “C definitely bends less.” Material composition can be described before a lift; a bending outcome cannot.
- Child try · 7 min. Card 102 routes identify P/C parts and one property question. Adult records what was actually inspected or described.
- Check · 4 min. Show a paper picture of the card hidden behind C. Child says not seeing backing from the front does not prove absent; source description matters.
- Exit · 2 min. Save material-part claim with source; no property result added.