School District Wide Events

I want to add events to the calendar such as Vacations, Holidays, Open Houses and I want them to show up on each schools calendar.  However, I want users to be able to book events as well and the approver would have the opportunity to approve or deny.  It seems presently when we put in the these big events, it blocks out the users ability to choose any rooms.  In many instances, the users are allowed to come in during vacation weeks, etc.  Any solution because how we are doing it now is not working.  When we used School Dude, the people could book it and then the approver would see the conflict and decide whether or not to process and let the user know or offer then other options.  Thanks.