The ISSL is a league that has been set-up between five schools: ICS, ISZL, ZIS, IS Basel, and TASIS.  These schools have always played friendly matches during the week and a cluster Saturdays.  Some of these games and clusters will now count towards the ISSL league championship standings.  One game between schools over the course of a season, either a weekday game or during the cluster Saturday, will count towards league standings in sports such as soccer, basketball, volleyball, etc.  Therefore, the season will be a four game schedule.  Other sports such as tennis will have a tournament style format on their cluster Saturday which will determine the ISSL champion.  The team with the best record in their four games or the winner of the cluster Saturday tournament will be crowned as ISSL champion for the year and will receive a championship plaque to display at the their school for the year.