What is a statement of theme?

Before you begin to answer this question you must first
remember:

-  Theme is a subject or main idea of a work of
literature.
-  Theme is NOT plot summary.
-  Theme statements do not
give advice (they do not contain you, should, ought, etc.)
-  Theme statements
should be supported by text throughout the work, not just one
section.

That said, here are some notes about how to write
a theme statement for ANY piece of literature.

1.  Make a
list of SUBJECTS covered in the text (not plot details but things like, relationships,
fighting, growing up, etc.)
2.  Choose one, or two that seem to relate to each
other.
3.  Ask, "What is the author trying to say about
(subject)?  *I like to put things through what I call the
"cause-effect" machine.  Make a list of all the things that either
caused the subject or the effects of the
subject.  You use plot here, but by examining the patterns, you can often answer the
bigger question: What is the author trying to say about (subject)?
4.  Answer
the question in #3 with a complete sentence.  This is your theme statement.  Using words
like causes or results in are often
helpful.
5.  Prove your theme statement with examples from the
plot.

A final word:

The key to
theme statements is to make them broad enough to be universally applicable (ie. to other
works of literature or perhaps even life itself) but not SO BROAD that they could be
virtually applied to absolutely any work of literature.

For
example (Think of Romeo and Juliet):

1.  Fighting always
leads to death.  (Too narrow in one sense, but too broad when you consider - what kind
of fighting?)
2.  Fighting can be a negative thing.  (Um, yes, duh. 
Obviously.  Way too broad.)
3.  Hasty decisions often lead to unnecessary
fighting, which can be disasterous.  (Just narrow enough, but still universally
applicable.)