best solution for scheduling sporting events and speakers for meetings.

Looking for advice on a calendar type plugin where I can list different events and details.

for one client I need the ability to schedule speakers (usually 2 for each meeting) on a bi monthly or weekly basis. Also need the ability to email or notify of any scheduling changes of this calendar to all members of the group.

My other client is school where we are looking for a better way to informa parents of any schedule changes, cancellations etc... of games and events. This would also need to have the ability to notify parents via text or email of thest changes.

I may have asked this in another thread but was unable to find it. I'm sure there is a way to find all posts I've started or participated but I'm lost on how to do this.

All help and suggestions are appreciated.