Most high school students in North Carolina attend their local schools or charter schools. However, there are public school options for students who attend low performing schools.
In North Carolina under NCLB (No Child Left Behind), students who go to a Title I School Improvement school may attend a higher performing school. A school gets a designation of Title I School Improvement if they haven't met AYP goals in the same subject for two or more years.
Here's a link to learn more about the public school choice options in North Carolina.