Your memoir is an exploration of an event. Your job is not only to recreate the experience for the reader. You should also be telling the story for a purpose. You should be trying to retell this story as a way to offer insight into the human condition as you have it figured out. This theme could be simple (I may have broken a window in that mudball fight in 3rd grade, but, in retrospect, it was just innocent childhood fun) to more sophisticated (In "Sink or Swim," the narrator cold swim helps her become aware of her own mortality. In "The Chase," Annie Dillard explores the delight of just throwing your self at something without any thought to your own safety.
Anyway...try to convey a life lesson. There are two types of themes:
- Explicit Theme - Near the end of the memoir, you come out and directly state the lesson you have learned from the experience.
- Implicit Theme - You never quite say it clearly, but the action in the story implies, or hints at, deeper meaning
It is more difficult to pull off an implicit theme. See what you can do.