See Strength of Schedule for an explanation. There are three sos calculations:
the 1st averages the opponents computer rating based on
 computer margin of victory "Reg In" and "ROM", the 2nd
 is similar to the first but instead of a simple average, it
 weighs games against stronger teams more heavily, and
 the 3rd is based on the RPI SOS formula used by the NCAA. This factor is not used in the power rating calculation.
          
      
   
     
   
           
           

Use the Report Scores link for both scores and missing games.
     
  
  
   
Rank Team                    Total  SOS Ave   SOS Wt Ave  SOS RPI    W  L  T
                             Games Rnk Value  Rnk Value  Rnk Value
 
   1 Bainbridge Island         19   1  60.94   1  30.14   1   0.53  16  3  0
   2 Curtis, WA                13   2  59.87   5  28.56   9   0.49   0 13  0
   3 Lake Sammamish            15   3  59.85   3  28.94   3   0.52  10  5  0
   4 Tacoma                    14   4  59.84   2  29.01   4   0.51   6  8  0
   5 Bellevue                  14   5  59.70   4  28.72   6   0.51   6  7  1
   6 Nathan Hale               13   6  59.39   6  28.18  12   0.49   1 12  0
   7 Forest Ridge              13   7  59.29   7  28.10  10   0.49   2 11  0
   8 Seattle Prep School       14   8  59.19   8  28.04   7   0.50   6  7  1
   9 Garfield                  13   9  59.15   9  27.97  13   0.49   3  9  1
  10 Snohomish                 15  10  59.03  10  27.84   5   0.51  12  3  0
  11 Holy Names Acad, WA       13  11  58.92  11  27.74  11   0.49   4  9  0
  12 Roosevelt, WA             13  12  58.73  12  27.54  14   0.49   6  6  1
  13 Lakeside School           16  13  58.67  14  27.17   2   0.53  16  0  0
  14 Mercer Island             14  14  58.58  13  27.29   8   0.50  10  4  0