averages all of the recruiting site rankings together into 1 composite ranking. Their rating scores break down basically as follows:

98 - 100: 5 star - consists of the top 30 or so prospects in the class (i.e. future 1st round draft picks)
90-97: 4 star - consists of the remaining top 300 prospects in the class (great pro potential)
80-89: 3 star - consists of the remaining top 10% of the recruiting class (likely starters, some pro potential)
79-below: 2 star - makes up the bulk of D1 rosters (role players, little pro potential)