The Referee Report includes a section to grade sportsmanship behavior exhibited during the game.

The Lineup and Referee Report forms are available at this (Microsoft Excel) document link:
WYSL Lineup+Report

An example question and format to be used is as follows:

Were parents/spectators for home/visiting team acting responsible and exhibiting sportsmanship behavior by encouraging and supporting positive behavior on the field?
Score as follows:

0 1 2 3
Highly Unsportsmanlike Behavior No Noticeable Behavior Supportive Behavior Very Supportive Type Behavior