Facebook is the most popular social media platform for local sporting clubs. It has been used by clubs to:
set up 'closed' (secure) discussion groups for coaches, teams, members, sponsor groups and so forth. Discussion within these groups is generally not public - it is retained within the group.
post club-related photos
[Cricket] announce team selections or ask about player availability
encourage light hearted exchanges ('banter') within the club
[Athletics] maintain links with other clubs (for instance, to know when they are running events that your members may be able to enter)
recognise special member achievements
list upcoming fixtures or events