Hypothetical test?

#1
I have been given the following assignment:

In a school district of approximately 38,000 students in 73 schools (40 elementary schools, 20 middle schools, and 13 high schools), there are high on-time high school graduation rates, but low rates of actual enrollment in college the summer following students' senior year. The new superintendent has created a task-force to visit model high schools in the district to serve as examples of best practice that principals will visit six times this year. Pretend you are a school evaluator and the superintendent has asked you to identify the most appropriate high school for the task force to visit first. He asks that you include the high school’s current college outcomes in the decision process, but that he will leave selection criteria ultimately up to you. What school do you pick and what statistical tests do you use to determine that?

The data file includes each high school's student population's gender, free/reduced lunch status, ESL status, special education status, students' State Math test score in grade 8, students' State Reading test score in grade 8, students' SAT Verbal, Math, and Writing scores, whether they earned a diploma at all, whether they earned a diploma within four years of starting high school, whether students matriculated to college at all/to a two-year college/to a four-year college during the fall following high school graduation, AND the number of days students attended any type of college/a two-year college/a four-year college within two years of high school.

I think it is best to develop some sort of HLM model and nest students within schools within the district, but I'm not sure which variables are the most important (I think all of the college outcomes should be included, but all the test scores from SAT, Math and Reading should probably be in there, as well as graduation vs. on-time graduation rates). I guess my question is how should I analyze the data to first differentiate among schools, and from there, what tests should I run to show that this high school actually is "the best"? I am very shaky with HLM so any advice is appreciated, thanks so much!!!