The county buildings are a no-go by county statute.
Hang on, what do you mean "county statute"? North Carolina has state preemption, so county-level laws don't mean anything. The only off-limits places are defined in GS §14-415.11(c). Those are:
(1) Areas prohibited by G.S. 14-269.2, 14-269.3, and 14-277.2.
(2) Areas prohibited by G.S. 14-269.4, except as allowed under G.S. 14-269.4(6).
(3) In an area prohibited by rule adopted under G.S. 120-32.1.
(4) In any area prohibited by 18 U.S.C. § 922 or any other federal law.
(5) In a law enforcement or correctional facility.
(6) In a building housing only State or federal offices.
(7) In an office of the State or federal government that is not located in a building exclusively occupied by the State or federal government.
(8) On any private premises where notice that carrying a concealed handgun is prohibited by the posting of a conspicuous notice or statement by the person in legal possession or control of the premises.
(1) describes educational property, as in bona fide schools governed by a school board, not simply places where somebody might conceivably learn something, so that doesn't count. (It also describes places where alcohol is served and places where admission is charged, but those sections have been repealed.)
(2) describes courthouses and the governor's mansions.
(3) describes the legislative building
(4) is all of the Federal prohibitions, so that's your post offices, Army Corps of Engineers land, etc.
The Science museum isn't a jail, and it doesn't house only state or federal offices (there may be those offices in that building, and to the extent that there are you can't carry in those specific areas, but the entire building is not off limits on that account).
The only item that might possibly apply is (8), but since it isn't private property you can stop reading there.
And even if it was, the signs they have are the generic "no weapons" signs; they don't mention concealed weapons specifically, so my contention is that they aren't legal postings anyway under that statute.
And even if you don't buy the it-doesn't-say-concealed argument, since 12/1/15 carrying past a Gunbusters sign has been an infraction, not even a misdemeanor. It's the same as a speeding ticket. So if you drove 50 in a 45 to get to the museum, then you can carry into the Museum just the same.
I'm not a lawyer, so I'm not trying to convince you to do anything you're not comfortable with, but my position is that you may keep calm and carry on at the Science Museum in Raleigh. And enjoy it, because it's a neat place to visit!
