LEED Project Registration

I am trying to register a new Elementary School that has LEED Silver as a certification goal.  The main school building is 117,540 SF.  There is also a Central Plant building on the site (approx 5400 SF).  During project registration, the rating system selector has options that include, a single building development registration or a multiple building registration.  Although it is not critical for the school district that the Central Plant should be LEED certified, I would like to know if the building that contains some mechanical equipment that services the main building should somehow have to be LEED certified?  Is this necesary?  Also where do we draw the LEED boundary if only the main building is going after certification and what are the credits that would be impacted by this. if any?