According to the website, Massey Ratings are based on statistical models. What I don't know is if they use only schools listed on highschoolsports.net ? Mr. Massey was a Virginia Tech grad school grad. Thesis and bio are on the website. His statistical models are used in the BCS. The formulas lost me, but the scatter graph was pretty.
Looks like his thesis has become a hobby that every kid (and parent!) who checks schedules and results on the highschoolsports.net sees rankings for many sports. Not a plug here, but highschoolsports.net has a notification system that emails me when there is a change in schedules (probably updated by the coach?)