Hair can be a subject when in examples below it
Gets large in the frame.
Displays a photographic them: "Diagonal" (girl scout) or "Unusual" (spikey
Covers the face, which makes the person abstract and archetypical.
Example, the whittling scout below.
See also how expert photgraphers portray Hair,
Boy Scout Troop 174, Yorktown, NY. Scouting
Photography Pages at http://troop174.info