'With experience comes an ability to handle complex themes. You grow up and do mature -- Martha Coolidge
Wrote A TASTE OF HONEY, a landmark play in the British theatre, when she was about 18 -- the same age as her central character.
Wrote his play MOON CHILDREN when he was 26, but used central characters who were finishing their last year in college. By the time he was 26, he'd written over 20 plays, most of them produced.
Wrote his first published novel, THE ACROBATS, when he was 19 and finished the manuscript when he was 21 using a number of characters who were about 6 years older than he was.
Teenage writers -- or those just over the hump of 20 -- who attract notice usually create an adult world viewed through the eyes of their young central character, a character who is often the writer's current age.
That's how the first three of these folks made their reputations. If you're that young, keep in mind that most people who buy theatre tickets are not much younger than their mid-20's. They've long since lost interest in the distressing problems of teenagers who can't frame those issues in terms of the larger world.
http://www.vcu.edu/arts/playwriting/