Target: make Source A in symbols with explicit Key 1; partial AC9TDIFK02. Ready: Key 1, blank three-place strip.
- Welcome · 3 min. “A circle can stand for our wave if we tell the reader.” These are invented meanings, not official signs.
- Model · 4 min. Read B. Match each symbol to its picture/prop. Adult models WAVE with a circle and reads the printed meaning; do not assume the icon explains itself.
- Together · 5 min. Read circle/square/triangle one place at a time. Ask whether a stranger without the key would necessarily know. “We can give them the key.”
- Child task · 7 min. Child builds/directs the entire A message under Key 1 and places the key beside it. Invite an exact spoken, signed or AAC read-back. Adult follows the child's choices.
- Notice · 4 min. Record three correspondences. If a square is read as FINISH, return to the exact key after saving the first response. Shape recognition and reading support remain separate.
- Close · 2 min. Child selects a label, “Pretend show key,” or asks an adult to label it. This is a data display, not a safety sign.