PLEASE NOTE: View calendar in Google Chrome in order to see posted events and activities.
Two options to sync calendars.
Download Google Apps Sync for Microsoft Outlook
is a plug-in for Outlook 2003, 2007, 2010 or 2013 that lets you use Outlook to manage your Google Apps mail, calendar and contacts — along with your Outlook notes, tasks, and journal entries.
Google Calendar has more details.