What is a major conflict that Rachel deals with throughout The Girl Who Fell from the Sky? How is it resolved?

In this Educator's opinion, the main conflict here can best be indicated by the phrase Rachel vs. race. 

Before the tragedy (and before she lost all of her immediate family), Rachel had no concept of the different problems that people face in a big, American city like Chicago or Portland.  Rachel was happily living on a military base out of the country; therefore, she had no idea that being "bi-racial" was any big deal...

In this Educator's opinion, the main conflict here can best be indicated by the phrase Rachel vs. race. 

Before the tragedy (and before she lost all of her immediate family), Rachel had no concept of the different problems that people face in a big, American city like Chicago or Portland.  Rachel was happily living on a military base out of the country; therefore, she had no idea that being "bi-racial" was any big deal to anyone in an American big city.  It isn't long, however, before she realizes that the children segregate themselves in to "white" and "black" groups and, worse, that Rachel doesn't fit in with either group.  Rachel has dark skin and blue eyes.  This is enough to exclude her.

I'm not the color of my skin. I'm a story. One with a past and a future unwritten.

Although this conflict is never fully resolved, Rachel does try to manage the conflict internally. The first way she tries to manage it is that she vows to be "just fine" in any situation.  While doing this, she creates her own categories to fit into, such as a girl who is interested in pursuing her studies.  Another way she tries to manage the conflict is through her relationship with Anthony Miller.  In her greater attempt to fit in, she even loses her virginity with him. 

In conclusion, the most prominent resolution between Rachel vs. race comes when she meets Jesse through a job at the Salvation Army.  Because Jesse is white (and because he knows a lot about being black), Rachel finds a friend who also doesn't fit in.  In a sense, the conflict is resolved when Rachel realizes she is not alone in her conflict.  Rachel realizes that this conflict exists with other people who are of other races as well.