Which grade level(s) are appropriate for teaching The Watsons Go to Birmingham-- 1963 by C. Curtis ? Please explain.

As with any other piece of literature, the readability
(reading level) of the text along with the content should be considered before assigning
a book to a child.  In The Watson's Go to Birmingham-- 1963, the important factor for
consideration is the setting of the book.  It takes place during the heart of the civil
rights movement, one of the most tumultuous times of United States history.  It tells
the story of a family who visit Birmingham, Alabama from their home in Flint, Michigan. 
The voice of the narrator, ten year old Kenny, is appealing to young readers.  I've
actually had students as young as third grade read the book and enjoy it for the plot. 
In order to understand the historical implications of the book, however, a child would
probably have to be a bit older.  Ideally, students in grades 5-8 would read and fully
appreciate the depth of a book such as this one.