What statistical test should I use?

Help!!! This is due tomorrow and it is the driving me nuts! I am conducting mock research and need to do an ysis section, but I have no clue where to start. My research is studying if there is a relationship between neighborhood socioeconomic status and academic achievement. The participants are in 10th and 11th grade, male and female, and race is controlled for black or white. Academic achievement is measured by GPA- Excellent: 3.5-4.0, Good: 2.5-3.49, Average: 1.5-2.49, Ping: 1.0-1.49, and Failing: 0. Neighborhood socioeconomic status is one of the places where i'm stuck. Do I operationally define it as a variable itself (1-low, 2-high) or do I need to break it down, i.e. income level and education level-and operationally define the two. Problem number two is figuring out which test (SPSS) to use for statistical ysis.