Strength of Scedule is simply taking the over/under number of games won or lost of their opponents. I know there is much more that goes into strength of schedule. But this isn't computer rankings.
Walhalla has played a number of 3A and 4A teams, but most of these teams were average or below average teams. If you remove one game against Greenville, The combined records of the other games against 3A and 4A competition is below .500 at 67-69.
Andrew Jackson has played a fairly tough schedule. It included North Myrtle beach (3A #3) and West Ashley (4A #11). But also included Lancaster at 3-16 and several 1A teams.
It all works out in the wash - - -