Event Sync for Facebook is a free open-source app that will sync your Facebook events to your Android calendar. It will create five new calendars:
* Events I'm Attending - for events that you marked yourself that you are 'Going' on Facebook
* Events I May Be Attending - for events that you marked yourself as 'Maybe' on Facebook
* Events I Have Not Responded To - for events that you were invited to but did not respond yet
* Events I Declined - for events that you marked yourself as 'Not Going' on Facebook
* Friends' Birthdays - sync birthdays of user's Facebook friends

You can configure reminders for events in each of those calendars independently. You can also configure how often the events should be synced.

Report problems: https://github.com/danvratil/FBEventSync/issues
Privacy policy: https://github.com/danvratil/FBEventSync/wiki/Privacy-Policy
Source code: https://github.com/danvratil/FBEventSync/