In King George we use Calendarwiz for our publicly shared calendar. It is a pretty good calendar application, but one drawback is that if you want to see school events you need to go to a separate location to look at school events unless you want to enter them all by hand into your calendar. If your calendar is capable of supporting iCal links you actually add the calendar so that it will update itself. The updating only occurs once every 24 hours, so the updates aren't instantaneous, but they do happen.

Calendarwiz doesn't make the process especially easy, but I've written some instructions on how to make it happen. I have several of these calendars working with my Google Calendar and they work flawlessly. It's handy to be able to look at school events in my calendar without switching back and forth.

https://docs.google.com/document/d/1QS3hAjliLNh7RC4pInyaCRDmtVtb_2_5tJNsfb0Nfpc/view