The reason you cannot find the answer is that Scout's nickname is "Scout." That is not the name she was born with, so this is a bit of a trick question! Throughout most of the book, Scout is addressed only by this nickname. However, her real name is given in the first chapter, provided by Miss Caroline, her teacher, on the first day of school. First, Scout explains to Miss Caroline,
Jem says my name's really Jean Louise Bullfinch instead of Finch (17).
So we might think that Scout is joking and Jem has made up this entire name. But as we read along, we see that Miss Caroline does address Scout as Jean Louise when she is trying to explain to Miss Caroline about Walter Cunningham's family background. Miss Caroline, who is already clearly exhausted by Scout, asks,
What is it, Jean Louise? (20)
This is how we know this is actually Scout's name, the name in which she was enrolled in school. I believe there are a few other references to "Jean Louise" in the book. Perhaps you can find them.
"Scout" is her nickname. Her given name (her real name!) is Jean Louise Finch.
Make sure you are clear on the terminology regarding names:
1. Your given name/real name is the one your parents gave you and put on your birth certificate.
2. A pseudonym is a false name or a pen name, usually used by people who write books using a name that is not their own.
3. A nickname is one given to you that is either a shortened form of your given name (such as Bobby for Robert) or a name used mostly among your family and friends (such as Mernie for Marilyn) or a descriptive name (such as Shorty or Curly). If used often enough, nicknames can seem like a person's own real name!