Second day on the same lesson — p.11, letters and their sounds in isolation. Do not re-teach it. Re-run the column and go at whatever the children were not accurate on yesterday.
Top teeth on your bottom lip, exactly like /f/. Turn your voice ON — vvvvv. Your lip will tickle.
They check it: Hand on your throat: /v/ buzzes, /f/ does not. Feel the tickle on your lip.
Not in Somali, Arabic. For those children this is a new physical skill, not a reminder. Do not let the column start until the mouth can make it.